From the very beginning, let’s define what we mean here by the word genome. This term itself was first proposed in 1920 by the German geneticist G. Winkler. Then there was already another scientific term - genotype, introduced into the arsenal of geneticists by V. Johansen back in 1909, by which was meant the totality of all the hereditary inclinations of a given specific cell or a given specific organism. Subsequently, Johansen himself said with surprise that his “word” unexpectedly materialized in the later emerging chromosome theory T. Morgana. But then he appeared new term- genome. Unlike genotype, this term was supposed to become characteristic of an entire species of organism, rather than a specific individual. And this became a new stage in the development of genetics.
IN biological dictionary concept genome is defined as a set of genes characteristic of a haploid (single) set of chromosomes of a given type of organism. This formulation does not sound entirely clear to a non-specialist, and most importantly, it is inaccurate in the modern understanding of the word. The basis of the genome is a molecule of deoxyribonucleic acid, well known in abbreviated form as DNA. After all, all genomes (DNA) contain at least two types of information: encoded information about the structure of messenger molecules (so-called RNA) and protein (this information is contained in genes), as well as instructions that determine the time and place of manifestation of this information during development and further life activity of the organism (this information is mainly located in intergenic regions, although partially in the genes themselves). The genes themselves occupy a very small part of the genome, but at the same time they form its basis. The information recorded in genes is a kind of “instruction” for the manufacture of proteins, the main building blocks of our body. “On the shoulders” of genes lies a huge responsibility for how each cell and the organism as a whole will look and work. They control our lives from the moment of conception to the very last breath, without them not a single organ functions, blood does not flow, the heart does not beat, the liver and brain do not work.
However, to fully characterize the genome, the information contained in it about the structure of proteins is insufficient. We also need data on the elements of the genetic apparatus that take part in the work ( expression) genes regulate their expression at different stages of development and in different life situations.
But even this is not enough for full definition genome. After all, the genome also contains elements that contribute to its self-reproduction ( replication), compact packaging of DNA in the nucleus, and some other still unclear regions, sometimes called “selfish” (that is, as if serving only for themselves). For all these reasons today, when we're talking about about the genome, usually mean the entire set of DNA sequences presented in the chromosomes of cell nuclei certain type organisms, including, of course, genes. In this book we will mean exactly this definition. At the same time, it should be remembered that some other structures (organelles) of the cell also contain genetic information necessary for the functioning of organisms. In particular, all animal organisms, including humans, also have a mitochondrial genome, that is, DNA molecules present in intracellular structures such as mitochondria and containing a number of so-called mitochondrial genes. The human mitochondrial genome is very small compared to the nuclear genome located on chromosomes, but nevertheless, its contribution to cellular metabolism is very significant.
It is clear that knowledge of the DNA structure alone is not at all sufficient for full description hereditary system of the cell. The following analogy is given to this conclusion in the literature: information about the number and shape of bricks cannot reveal the design of the Gothic cathedral and the progress of its construction. In more in a broad sense The hereditary system of a cell is made up not only of the DNA structure, but also of its other components, the totality of which and environmental factors determine how the genome will work, how the course of individual development will proceed, and how the resulting organism will live later.
Human genome- genome of a biological species Homosapiens. Most normal human cells contain a full set of 46 chromosomes that make up the genome: 44 of them do not depend on sex (autosomal chromosomes), and two - the X chromosome and the Y chromosome - determine sex (XY in men or XX in women). Chromosomes in total contain approximately 3 billion base pairs of DNA nucleotides, forming 20,000-25,000. During the implementation of the Human Genome Project, the contents of the chromosomes at the interphase stage in the cell nucleus (euchromatin substance) were written out as a sequence of symbols. Currently, this sequence is actively used throughout the world in biomedicine. Research has revealed that the human genome contains significantly smaller number genes than expected at the beginning of the project. Only for 1.5% of the total material was it possible to determine the function; the rest is so-called junk DNA. This 1.5% includes genes that encode RNA and proteins, as well as their regulatory sequences, introns, and possibly pseudogenes.
The human genome consists of 23 pairs of chromosomes ( in total 46 chromosomes), where each chromosome contains hundreds of genes separated intergenic space. The intergenic space contains regulatory regions and non-coding DNA.
There are 23 pairs of different chromosomes in the genome: 22 of them do not affect sex, and two chromosomes (X and Y) determine sex. Chromosomes 1 to 22 are numbered in order of decreasing size. Somatic cells usually have 23 chromosome pairs: one copy of chromosomes 1 to 22 from each parent, respectively, as well as an X chromosome from the mother and a Y or X chromosome from the father. In total, it turns out that a somatic cell contains 46 chromosomes.
According to the results of the Human Genome Project, the number of genes in the human genome is about 28,000 genes. The initial estimate was more than 100 thousand genes. Due to improvements in gene search methods (gene prediction), a further reduction in the number of genes is expected.
Interestingly, the number of human genes is not much greater than the number of genes in simpler model organisms, for example, the roundworm Caenorhabditiselegans or flies Drosophilamelanogaster. This is due to the fact that alternative splicing is widely represented in the human genome. Alternative splicing allows you to obtain several different protein chains from one gene. As a result, the human proteome appears to be significantly larger than the proteome of the organisms examined. Most human genes have multiple exons, and introns are often significantly longer than the bordering exons in the gene.
Genes are unevenly distributed across chromosomes. Each chromosome contains gene-rich and gene-poor regions. These regions correlate with chromosomal bands (bands across the chromosome that are visible under a microscope) and with CG-rich regions. At present, the significance of this uneven distribution of genes is not fully understood.
In addition to protein-coding genes, the human genome contains thousands of RNA genes, including transfer RNA (tRNA), ribosomal RNA, microRNA, and other non-protein-coding RNA sequences.
Related information.
It was seven years ago - June 26, 2000. At a joint press conference with the participation of the US President and the British Prime Minister, representatives of two research groups - International Human Genome Sequencing Consortium(IHGSC) and Celera Genomics- announced that work on deciphering the human genome, which began in the 70s, has been successfully completed, and its draft version has been compiled. A new episode of human development has begun - the post-genomic era.
What can deciphering the genome give us, and are the funds and efforts spent worth the results achieved? Francis Collins ( Francis S. Collins), supervisor American program The Human Genome, in 2000, gave the following forecast for the development of medicine and biology in the post-genomic era:
- 2010 - genetic testing, preventive measures, reducing the risk of diseases, and gene therapy for up to 25 hereditary diseases. Nurses are beginning to perform medical genetic procedures. Preimplantation diagnostics are widely available, and the limitations of this method are actively discussed. The United States has laws to prevent genetic discrimination and respect privacy. Practical applications of genomics are not accessible to everyone, this is especially true in developing countries Oh.
- 2020 - drugs for diabetes, hypertension and other diseases, developed on the basis of genomic information, are appearing on the market. Cancer therapies are being developed that specifically target the properties of cancer cells in specific tumors. Pharmacogenomics is becoming a common approach for the development of many drugs. Changing the diagnostic method mental illness, the emergence of new methods of treating them, changing the attitude of society towards such diseases. Practical applications of genomics are still not available everywhere.
- 2030 - determination of the nucleotide sequence of the entire genome of an individual will become a routine procedure, costing less than $1000. Genes involved in the aging process have been cataloged. Clinical trials are being conducted to increase the maximum lifespan of humans. Laboratory experiments on human cells have been replaced by experiments on computer models. Mass movements of opponents are intensifying advanced technologies in the USA and other countries.
- 2040
- All generally accepted health measures are based on genomics. Predisposition to most diseases is determined (even before birth). Effective preventative medicine tailored to the individual is available. Diseases are detected at early stages through molecular monitoring.
Gene therapy is available for many diseases. Replacing drugs with gene products produced by the body in response to therapy. Average duration life will reach 90 years due to improved socio-economic conditions. There is serious debate about man's ability to control his own evolution.
Inequality in the world persists, creating tension at the international level.
As can be seen from the forecast, genomic information in the near future may become the basis for the treatment and prevention of many diseases. Without information about his genes (and it fits on a standard DVD), a person in the future will only be able to cure a runny nose from some healer in the jungle. Does this seem fantastic? But once upon a time, universal vaccination against smallpox or the Internet were just as fantastic (note that it did not exist in the 70s)! In the future, the child’s genetic code will be given to parents in the maternity hospital. Theoretically, with such a disk, treatment and prevention of any ailments of an individual person will become a mere trifle. Professional doctor will be able to the utmost short time make a diagnosis, prescribe effective treatment, and even determine the likelihood of various diseases appearing in the future. For example, modern genetic tests can already accurately determine the degree of a woman’s predisposition to breast cancer. Almost certainly, in 40–50 years, not a single self-respecting doctor without genetic code will not want to “treat blindly” - just as today surgery cannot do without an X-ray.
Let's ask ourselves the question - is what was said reliable, or maybe in reality everything will be the other way around? Will people finally be able to overcome all diseases and will they achieve universal happiness? Alas. Let's start with the fact that the Earth is small, and there is not enough happiness for everyone. In truth, it is not enough for even half the population of developing countries. “Happiness” is intended mainly for states that are developed in terms of science, in particular biological sciences. For example, a technique with which you can “read” the genetic code of any person has long been patented. This is a well-developed automated technology - although it is expensive and very subtle. If you want, buy a license, or if you want, invent it new technique. But not all countries have enough money for such development! As a result, a number of states will have medicine that is significantly ahead of the level of the rest of the world. Naturally, in underdeveloped countries the Red Cross will build charitable hospitals, hospitals and genomic centers. And gradually this will lead to the fact that the genetic information of patients in developing countries (which are the majority) will be concentrated in two or three powers that finance this charity. It’s hard to even imagine what can be done with such information. Maybe it's okay. However, another outcome is also possible. The battle over priority that accompanied genome sequencing illustrates the importance of the availability of genetic information. Let's briefly recall some facts from the history of the Human Genome Program.
Opponents of genome decoding considered the task unrealistic, because human DNA is tens of thousands of times longer than the DNA molecules of viruses or plasmids. Main argument was against: “ the project will require billions of dollars, which other areas of science will miss, so genome project will slow down the development of science as a whole. But if money is found and the human genome is deciphered, then the resulting information will not justify the costs...“However, James Watson, one of the discoverers of the structure of DNA and the ideologist of the program for total reading of genetic information, wittily retorted: “ It's better not to catch a big fish than not to catch a small one", . The scientist’s argument was heard - the genome problem was brought up for discussion in the US Congress, and as a result, the national Human Genome program was adopted.
IN American city Bethesda, near Washington, is one of HUGO's focal points ( Human Genome Organization). The center coordinates scientific work on the topic “Human Genome” in six countries - Germany, England, France, Japan, China and the USA. Scientists from many countries of the world joined the work, united in three teams: two interstate - American Human Genome Project and British from Wellcome Trust Sanger Institute- and a private corporation from Maryland, which entered the game a little later - Celera Genomics. By the way, this is perhaps the first case in biology when such high level a private firm competed with intergovernmental organizations.
The struggle took place using colossal means and capabilities. As noted some time ago Russian experts, Celera stood on the shoulders of the Human Genome program, that is, it used what had already been done as part of the global project. Really, Celera Genomics I joined the program not at first, but when the project was already in full swing. However, experts from Celera improved the sequencing algorithm. In addition, a supercomputer was built on their order, which made it possible to add the identified “building blocks” of DNA into the resulting sequence faster and more accurately. Of course, all this did not give the company Celera unconditional advantage, but forced her to be considered as a full participant in the race.
Appearance Celera Genomics tensions sharply increased - those who were employed in government programs felt fierce competition. In addition, after the creation of the company, the question of the efficiency of using public investment became acute. At the head Celera became Professor Craig Venter ( Craig Venter) who had extensive experience scientific work under the state program “Human Genome”. It was he who said that all public programs are ineffective and that his company sequences the genome faster and cheaper. And then another factor appeared - large pharmaceutical companies caught on. The fact is that if all information about the genome is in the public domain, they will lose intellectual property, and there will be nothing to patent. Concerned about this, they invested billions of dollars in Celera Genomics (which was probably easier to negotiate with). This further strengthened her position. In response to this, the teams of the interstate consortium urgently had to increase the efficiency of genome decoding work. At first the work went uncoordinated, but then achievements were achieved certain forms coexistence - and the race began to pick up pace.
The finale was beautiful - the competing organizations, by mutual agreement, simultaneously announced the completion of work on deciphering the human genome. This happened, as we already wrote, on June 26, 2000. But the time difference between America and England brought the United States to first place.
Figure 1. The “Race for the Genome,” which involved an intergovernmental and private company, formally ended in a “draw”: both groups of researchers published their achievements almost simultaneously. Head of a private company Celera Genomics Craig Venter published his work in the journal Science co-authored with ~270 scientists who worked under his supervision. The work, carried out by the International Human Genome Sequencing Consortium (IHGSC), was published in the journal Nature, and the full list of authors numbers about 2,800 people working in nearly three dozen centers around the world.
The research lasted a total of 15 years. Creating the first “draft” version of the human genome cost $300 million. However, all research on this topic, including comparative analyzes and solutions to a number of ethical problems, about three billion dollars were allocated. Celera Genomics invested about the same amount, although she spent it in just six years. The price is colossal, but this amount is insignificant in comparison with the benefits that the developer country will receive from the expected soon final victory over dozens of serious diseases. In an early October 2002 interview with The Associated Press, President Celera Genomics Craig Venter said one of his non-profit organizations plans to produce CDs containing as much information as possible about a client's DNA. The preliminary cost of such an order is more than 700 thousand dollars. And one of the discoverers of the structure of DNA - Dr. James Watson - was already given two DVDs with his genome worth a total of $1 million this year - as we see, prices are falling. So, the vice president of the company 454 Life Sciences Michael Egholm ( Michael Egholm) reported that the company will soon be able to increase the price of decryption to 100 thousand dollars.
Widespread fame and large-scale funding are a double-edged sword. On the one hand, due to unlimited funds, work progresses easily and quickly. But on the other hand, the result of the research should turn out the way it is ordered. By the beginning of 2001, more than 20 thousand genes had been identified with 100% certainty in the human genome. This figure turned out to be three times less than predicted just two years earlier. A second team of researchers from the US National Institute for Genomic Research, led by Francis Collins, independently obtained the same results - between 20 and 25 thousand genes in the genome of each human cell. However, uncertainty in the final estimates was introduced by two other international joint scientific project. Dr. William Heseltine (chief executive) Human Genome Studies) insisted that their bank contained information about 140 thousand genes. And he is not going to share this information with the world community for now. His company has invested money in patents and plans to make money from the information obtained as it relates to genes for widespread human diseases. Another group claimed that there were 120,000 identified human genes and also insisted that this figure reflected the total number of human genes.
Here it is necessary to clarify that these researchers were engaged in deciphering the DNA sequence not of the genome itself, but of DNA copies of informational (also called template) RNA (mRNA or mRNA). In other words, not the entire genome was studied, but only that part of it that is recoded by the cell into mRNA and directs the synthesis of proteins. Since one gene can serve as a template for the production of several different types of mRNA (which is determined by many factors: cell type, stage of development of the organism, etc.), then the total number of all different mRNA sequences (and this is exactly what the patented Human Genome Studies) will be significantly larger. Most likely, using this number to estimate the number of genes in the genome is simply incorrect.
Obviously, hastily “privatized” genetic information will be carefully checked in the coming years until the exact number of genes finally becomes generally accepted. But what is alarming is the fact that in the process of “cognition” everything that can be patented is patented. It’s not even the skin of a dead bear, but in general everything that was in the den was divided up! By the way, today the debate has slowed down, and the human genome officially contains only 21,667 genes (NCBI version 35, dated October 2005). It should be noted that for now most of the information remains publicly available. Now there are databases that accumulate information about the structure of the genome not only of humans, but also of the genomes of many other organisms (for example, EnsEMBL). However, attempts to obtain exclusive rights to use any genes or sequences for commercial purposes have always been, are now and will continue to be made.
Today, the main goals of the structural part of the program have already been largely fulfilled - the human genome has been read almost completely. The first, "draft" version of the sequence, published in early 2001, was far from perfect. It was missing approximately 30% of the genome sequence as a whole, of which about 10% was the sequence of the so-called euchromatin- gene-rich and actively expressed regions of chromosomes. According to recent estimates, euchromatin makes up approximately 93.5% of the entire genome. The remaining 6.5% comes from heterochromatin- these regions of chromosomes are poor in genes and contain a large number of repeats, which pose serious difficulties for scientists trying to read their sequence. Moreover, DNA in heterochromatin is thought to be inactive and not expressed. (This may explain the “inattention” of scientists to the remaining “small” percentages of the human genome.) But even the “draft” versions of euchromatic sequences available in 2001 contained a large number of breaks, errors, and incorrectly connected and oriented fragments. Without in any way detracting from the significance of this “draft” for science and its applications, it is worth noting, however, that the use of this preliminary information in large-scale experiments analyzing the genome as a whole (for example, when studying the evolution of genes or general organization genome) revealed many inaccuracies and artifacts. Therefore, further and no less painstaking work, “the last steps”, was absolutely necessary.
Figure 2. Left: Automated line for preparing DNA samples for sequencing at the Whitehead Institute Genomic Research Center. On right: A laboratory in , filled with machines for high-throughput decoding of DNA sequences.
Completing the decryption took several more years and nearly doubled the cost of the entire project. However, already in 2004 it was announced that euchromatin was 99% read with an overall accuracy of one error per 100,000 base pairs. The number of breaks has decreased by 400 times. Accuracy and completeness of reading has become sufficient for an effective search for genes responsible for this or that hereditary disease(eg diabetes or breast cancer). In practical terms, this means that researchers no longer have to go through the labor-intensive process of confirming the sequences of the genes they are working with, since they can rely entirely on a specific, publicly available sequence of the entire genome.
Thus, the original project plan was significantly exceeded. Has this helped us in understanding how our genome is structured and works? Undoubtedly. Authors of the article in Nature, in which the “final” (as of 2004) version of the genome was published, carried out several analyzes using it, which would have been absolutely meaningless if they had only a “draft” sequence on hand. It turned out that more than a thousand genes were “born” quite recently (by evolutionary standards, of course) - in the process of doubling the original gene and the subsequent independent development of the daughter gene and the parent gene. And just under forty genes have recently “died”, having accumulated mutations that made them completely inactive. Another article published in the same issue of the magazine Nature, directly points out the shortcomings of the method used by scientists from Celera. The consequence of these shortcomings was the omission of numerous repeats in the read DNA sequences and, as a result, an underestimated length and complexity of the entire genome. To avoid repeating similar mistakes in the future, the authors of the article proposed using a hybrid strategy - a combination of a highly effective approach used by scientists from Celera, and the comparatively slow and labor-intensive, but also more reliable method used by the IHGSC researchers.
Where will the unprecedented Human Genome study go next? Something can be said about this now. Founded in September 2003, the international consortium ENCODE ( ENCyclopaedia Of DNA Elements) set as its goal the discovery and study of “control elements” (sequences) in the human genome. Indeed, 3 billion base pairs (namely, the length of the human genome) contain only 22 thousand genes, scattered in this ocean of DNA in a manner incomprehensible to us. What controls their expression? Why do we need such an excess of DNA? Is it really ballast, or does it still manifest itself, possessing some unknown functions?
To begin with, as a pilot project, ENCODE scientists took a "closer look" at a sequence representing 1% of the human genome (30 million base pairs), using the latest equipment for molecular biology research. The results were published in April this year in Nature. It turned out that most of the human genome (including regions previously considered “silent”) serves as a template for the production of various RNAs, many of which are not informational because they do not encode proteins. Many of these “non-coding” RNAs overlap with “classical” genes (sections of DNA that code for proteins). Another unexpected result was how the regulatory DNA regions were located relative to the genes whose expression they controlled. The sequences of many of these regions changed little during evolution, while other regions thought to be important for cell control mutated and changed at unexpectedly high rates during evolution. All these findings have raised a large number of new questions, the answers to which can only be obtained in further research.
Another task, the solution of which will be a matter of the near future, is to determine the sequence of the remaining “small” percentages of the genome that make up heterochromatin, i.e., gene-poor and repeat-rich DNA sections necessary for the doubling of chromosomes during cell division. The presence of repetitions makes the task of deciphering these sequences insoluble for existing approaches, and therefore requires the invention of new methods. Therefore, do not be surprised when another article is published in 2010, announcing the “finishing” of deciphering the human genome - it will talk about how heterochromatin was “hacked.”
Of course, now we only have at our disposal a certain “average” version of the human genome. Figuratively speaking, today we have only the most general description of the design of a car: engine, chassis, wheels, steering wheel, seats, paint, upholstery, gasoline and oil, etc. A closer examination of the result obtained indicates that there are years of work ahead to clarify our knowledge for each specific genome. The Human Genome Program has not ceased to exist; it is only changing its orientation: from structural genomics there is a transition to functional genomics, designed to determine how genes are controlled and work. Moreover, all people differ at the gene level in the same way that the same car models differ various options executions of the same units. Not only individual bases in the gene sequences of two different people may differ, but the number of copies of large DNA fragments, sometimes including several genes, can vary greatly. This means that work on a detailed comparison of the genomes of, say, representatives of different human populations, ethnic groups, and even healthy and sick people is coming to the fore. Modern technologies make it possible to quickly and accurately carry out such comparative analyzes, but ten years ago no one dreamed of this. Another international scientific association is studying structural variations in the human genome. In the USA and Europe, significant funds are allocated to finance bioinformatics - a young science that arose at the intersection of computer science, mathematics and biology, without which it is impossible to understand the boundless ocean of information accumulated in modern biology. Bioinformatic methods will help us answer many most interesting questions- “how did human evolution occur?”, “which genes determine certain characteristics of the human body?”, “which genes are responsible for predisposition to diseases?” You know what the English say: “ This is the end of the beginning” - “This is the end of the beginning.” This phrase exactly reflects current situation. The most important thing begins and - I am absolutely sure - the most interesting: the accumulation of results, their comparison and further analysis.
« ...Today we are releasing the first edition of the “Book of Life” with our instructions, - Francis Collins said on the Rossiya TV channel. - We will turn to it for tens, hundreds of years. And soon people will wonder how they could manage without this information.».
Another point of view can be illustrated by quoting Academician V. A. Kordyum:
“...The hopes that new information about the functions of the genome will be completely open are purely symbolic. It can be predicted that gigantic centers will arise (on the basis of existing ones) that will be able to connect all the data into one coherent whole, a kind of electronic version of Man and implement it practically - into genes, proteins, cells, tissues, organs and anything else. But what? Pleasant to whom? For what? In the process of work on the “human genome” program, methods and equipment for determining the primary DNA sequence were rapidly improved. IN largest centers it turned into a kind of factory activity. But even at the level of individual laboratory devices (or rather, their complexes), such advanced equipment has already been created that it is capable of determining in three months a DNA sequence that is equal in volume to the entire human genome. It is not surprising that the idea of identifying genomes arose (and immediately began to be rapidly implemented) individual people. Of course, it is very interesting to compare the differences of different individuals at the level of their fundamental principles. The benefits of such a comparison are also undoubted. It will be possible to determine who has what abnormalities in the genome, predict their consequences and eliminate what can lead to disease. Health will be guaranteed, and life will be extended quite significantly. This is on the one hand. On the other hand, everything is not at all obvious. Obtaining and analyzing the entire heredity of an individual means obtaining a complete, comprehensive biological dossier on him. It, if desired by the one who knows him, will allow him to do whatever he wants with a person just as comprehensively. According to the already known chain: a cell is a molecular machine; a person is made up of cells; the cell in all its manifestations and in the entire range of possible responses is recorded in the genome; The genome can already be manipulated to a limited extent today, and in the foreseeable future it can be manipulated in almost any way...»
However, it is probably too early to be afraid of such gloomy forecasts (although you certainly need to know about them). To implement them, it is necessary to completely rebuild many social and cultural traditions. The doctor said very well about this in an interview biological sciences Mikhail Gelfand, and. O. Deputy Director of the Institute for Information Transmission Problems of the Russian Academy of Sciences: “ ...if you have, say, one of the five genes that predetermine the development of schizophrenia, then what could happen if this information - your genome - fell into the hands of your potential employer who doesn’t understand anything about genomics!(and as a result, they may not hire you, considering it risky; and this despite the fact that you do not and will not have schizophrenia - author's note.) Another aspect: with the advent of individualized medicine based on genomics, insurance medicine will completely change. After all, it is one thing to provide for unknown risks, and another thing to provide for completely certain ones. To be honest, the entire Western society as a whole, not only Russian, is not ready for the genomic revolution now...” .
Indeed, to use wisely new information, you need to understand it. And in order to understand the genome is not easy to read, this is far from enough - it will take us decades. A very complex picture is emerging, and in order to understand it, we will need to change many stereotypes. Therefore, in fact, deciphering the genome is still ongoing and will continue. And whether we stand aside or finally become active participants in this race depends on us.
Literature
- Kiselev L. (2001). New Biology began in February 2001. "Science and life";
- Kiselev L. (2002). The second life of the genome: from structure to function. "Knowledge is power". 7 ;
- Ewan Birney, The ENCODE Project Consortium, John A. Stamatoyannopoulos, Anindya Dutta, Roderic Guigó, et. al.. (2007). Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project. Nature. 447 , 799-816;
- Lincoln D. Stein. (2004). Human genome: End of the beginning. Nature. 431 , 915-916;
- Gelfand M. (2007). Postgenomic era. "Commercial Biotechnology".
The content of the article
HUMAN GENOME, an international program whose ultimate goal is to determine the nucleotide sequence (sequencing) of the entire human genomic DNA, as well as the identification of genes and their localization in the genome (mapping). The original idea for the project originated in 1984 among a group of physicists working for the US Department of Energy who wanted to move on to a different problem after completing nuclear projects.
In 1988, the Joint Committee, which included the US Department of Energy and the National Institutes of Health, introduced an extensive project whose tasks - in addition to sequencing the human genome - included a comprehensive study of the genetics of bacteria, yeast, nematodes, fruit flies and mice (these organisms have been widely used as model organisms). systems in the study of human genetics). In addition, a detailed analysis of ethical and social problems arising in connection with work on the project. The committee managed to convince Congress to allocate $3 billion for the project (one DNA nucleotide for one dollar), in which the leader of the project played a significant role Nobel laureate J.Watson. Soon other countries joined the project (England, France, Japan, etc.). In Russia, in 1988, Academician A.A. Baev came up with the idea of sequencing the human genome, and in 1989, it was organized in our country science Council under the Human Genome program.
In 1990, the International Human Genome Organization (HUGO) was created, the vice-president of which was academician A.D. Mirzabekov for several years. From the very beginning of work on the genome project, scientists agreed on the openness and accessibility of all information received for its participants, regardless of their contribution and nationality. All 23 human chromosomes were divided among the participating countries. Russian scientists had to study the structure of the 3rd and 19th chromosomes. Soon, funding for this work in our country was cut, and Russia did not take any real part in sequencing. The genomic research program in our country has been completely restructured and focused on a new area - bioinformatics, which is trying to mathematical methods understand and comprehend everything that has already been deciphered.
The work was supposed to be completed in 15 years, i.e. around 2005. However, the sequencing speed increased every year, and if in the early years it amounted to several million nucleotide pairs per year around the world, then at the end of 1999 the private American company Celera, headed by J. Venter, deciphered at least 10 million nucleotide pairs per day. This was achieved due to the fact that sequencing was carried out by 250 robotic installations; they worked around the clock, functioned automatically and immediately transferred all information directly to data banks, where it was systematized, annotated and made available to scientists around the world. In addition, Celera made extensive use of data obtained as part of the Project by other participants, as well as various types of preliminary data. On April 6, 2000, a meeting of the US Congress Committee on Science took place, at which Venter stated that his company had completed deciphering the nucleotide sequence of all significant fragments of the human genome and that preliminary work to compile the nucleotide sequence of all genes (it was assumed that there are 80 thousand of them and that they contain approximately 3 billion nucleotides) will be completed in 3–6 weeks, i.e. much earlier than planned.
The report was made in the presence of a representative of HUGO, the largest sequencing specialist, Dr. R. Waterson. The genome deciphered by Celera belonged to an anonymous man, i.e. contained both X and Y chromosomes, and HUGO used material obtained from different people in their studies. Negotiations were held between Venter and HUGO to jointly publish the results, but they ended in vain due to disagreements over what should be considered the completion of genome sequencing. According to Celera, this can only be said if the genes are fully sequenced and it is known how the deciphered segments are located in the DNA molecule. This requirement was met by the Celera results, while the HUGO results did not allow us to unambiguously determine the relative position of the deciphered sections. As a result, in February 2001, in special issues of two most authoritative scientific journals, “Science” and “Nature”, the results of the “Celera” and HUGO studies were published separately and the complete nucleotide sequences of the human genome were presented, covering about 90% of its length.
General biological significance of the research conducted within the framework of the Project.
Research on the human genome has led to the sequencing of the genomes of a huge number of other, much simpler organisms; Without the genomic project, this data would have been obtained much later and in a much smaller volume. They are being deciphered at an ever-increasing pace. The first major success was the complete mapping of the bacterial genome in 1995. Haemophilus influenzae, later the genomes of more than 20 bacteria were completely deciphered, including the causative agents of tuberculosis, typhus, syphilis, etc. In 1996, the genome of the first eukaryotic cell (a cell containing a formed nucleus) was mapped - yeast, and in 1998 the genome of a multicellular organism - round worm Caenorhabolits elegans(nematodes). The genome of the first insect, the fruit fly Drosophila, and the first plant, Arabidopsis, have been deciphered. In humans, the structure of the two smallest chromosomes has already been established - the 21st and 22nd. All this created the basis for the creation of a new direction in biology - comparative genomics.
Knowledge of the genomes of bacteria, yeast and nematodes gives evolutionary biologists unique opportunity comparisons not of individual genes or their ensembles, but of entire genomes. These gigantic volumes of information are just beginning to be comprehended, and there is no doubt that new concepts will emerge in biological evolution. Thus, many “personal” genes of the nematode, in contrast to the genes of yeast, are most likely associated with intercellular interactions that are characteristic specifically for multicellular organisms. Humans have only 4–5 times more genes than nematodes; therefore, some of their genes must have “relatives” among the now known genes of yeast and worms, which facilitates the search for new human genes. The functions of unknown nematode genes are much easier to study than those of similar human genes: it is easy to make changes (mutations) in them or disable them, while simultaneously tracking changes in the properties of the organism. Having identified the biological role of gene products in the worm, it is possible to extrapolate these data to humans. Another approach is to suppress gene activity using specific inhibitors and monitor changes in the body's behavior.
The question of the relationship between coding and non-coding regions in the genome seems very interesting. As computer analysis shows, C.elegans approximately equal shares– 27 and 26%, respectively, are occupied in the genome by exons (regions of a gene in which information about the structure of a protein or RNA is recorded) and introns (regions of a gene that do not carry such information and are excised during the formation of mature RNA). The remaining 47% of the genome is made up of repeats, intergenic regions, etc., i.e. on DNA with unknown functions. Comparing these data with the yeast genome and the human genome, we see that the proportion of coding regions per genome decreases sharply during evolution: in yeast it is very high, in humans it is very small. There is a paradox: the evolution of eukaryotes from lower to higher forms is associated with the “dilution” of the genome - per unit length of DNA there is everything less information about the structure of proteins and RNA and more and more information “about nothing”, in fact simply not understood and unread by us. Many years ago F. Crick, one of the authors of “ double helix” - DNA models, - called this DNA “selfish” or “junk”. It is possible that some part of human DNA really belongs to this type, but it is now clear that the main part of the “selfish” DNA is preserved during evolution and even increases, i.e. for some reason it gives its owner evolutionary advantages. No explanation for this phenomenon currently exists, and without detailed analysis It is impossible to give them nucleotide sequences of genomic DNA.
Another important result, which has general biological (and practical) significance - genome variability. Generally speaking, the human genome is highly conserved. Mutations in it can either damage it, and then they lead to one or another defect or death of the organism, or turn out to be neutral. The latter are not subject to selection because they do not have phenotypic manifestations. However, they can spread in the population, and if their share exceeds 1%, then they speak of polymorphism (diversity) of the genome. There are many regions in the human genome that differ by just one or two nucleotides, but are passed on from generation to generation. On the one hand, this phenomenon hinders the researcher, since he has to figure out whether there is a true polymorphism or is it just a sequencing error, and on the other hand, it creates a unique opportunity for the molecular identification of an individual organism. From a theoretical point of view, genomic variability provides the basis for population genetics, which was previously based on purely genetic and statistical data.
Practical applications.
Both scientists and society place their greatest hopes on the possibility of using the results of sequencing the human genome to treat genetic diseases. To date, many genes have been identified in the world that are responsible for many human diseases, including such serious ones as Alzheimer's disease, cystic fibrosis, Duchenne muscular dystrophy, Huntington's chorea, hereditary breast and ovarian cancer. The structures of these genes have been completely deciphered, and they themselves have been cloned. Back in 1999, the structure of chromosome 22 was established and the functions of half of its genes were determined. Defects in them are associated with 27 various diseases, including schizophrenia, myeloid leukemia and trisomy 22 - the second most common cause of spontaneous abortion. The most effective way The treatment for such patients would be to replace the defective gene with a healthy one. To do this, firstly, it is necessary to know the exact localization of the gene in the genome, and secondly, so that the gene gets into all cells of the body (or at least the majority), and this is when modern technologies impossible. In addition, even the desired gene that enters the cell is instantly recognized by it as foreign, and it tries to get rid of it. Thus, only part of the cells can be “cured” and only temporarily. Another serious obstacle to the use of gene therapy is the multigenic nature of many diseases, i.e. their conditioning by more than one gene. So, mass application gene therapy is unlikely to be expected in the near future, although successful examples this kind already exists: it was possible to achieve significant relief in the condition of a child suffering from severe congenital immunodeficiency by introducing normal copies of the damaged gene into him. Research in this area is being conducted all over the world, and perhaps success will be achieved sooner than expected, as happened with the sequencing of the human genome.
Another important application of sequencing results is the identification of new genes and the identification of those among them that cause predisposition to certain diseases. Thus, there is evidence of a genetic predisposition to alcoholism and drug addiction; seven genes have already been discovered, defects in which lead to substance abuse. This will allow for early (and even prenatal) diagnosis of diseases for which a predisposition has already been established.
Another phenomenon will undoubtedly find wide application: it was discovered that different alleles of the same gene can cause different reactions of people to drugs. Pharmaceutical companies plan to use this data to produce drugs intended different groups patients. This will help avoid side effects therapy, reduce millions of costs. A whole new branch is emerging - pharmacogenetics, which studies how certain features of DNA structure can affect the effectiveness of treatment. Completely new approaches to creating medicines, based on the discovery of new genes and the study of their protein products. This will allow us to move from the ineffective method of “trial and error” to the targeted synthesis of medicinal substances.
An important practical aspect of genome variability is the possibility of individual identification. The sensitivity of “genomic fingerprinting” methods is such that one drop of blood or saliva, one hair is enough to establish family ties between people with absolute certainty (99.9%). After sequencing the human genome, this method, which now uses not only specific markers in DNA, but also single-nucleotide polymorphism, will become even more reliable. Genome variability gave rise to the direction of genomics – ethnogenomics. Ethnic groups, inhabiting the Earth, have some group genetic characteristics characteristic of a given ethnic group. The information obtained in some cases can confirm or refute certain hypotheses circulating within disciplines such as ethnography, history, archeology, and linguistics. Another interesting direction– paleogenomics, which deals with the study of ancient DNA extracted from remains found in burial grounds and burial mounds.
Problems and concerns.
The financing of the “genomic race” and the participation of thousands of specialists in it were based primarily on the postulate that deciphering the nucleotide sequence of DNA could solve fundamental problems of genetics. It turned out, however, that only 30% of the human genome encodes proteins and is involved in the regulation of gene action during development. What are the functions of the remaining sections of DNA and whether they exist at all remains completely unclear. About 10% of the human genome consists of so-called Alu-elements 300 bp long. They appeared from nowhere in the course of evolution among primates, and only among them. Once they reached humans, they multiplied to half a million copies and were distributed along the chromosomes in the most bizarre way, either forming clumps or interrupting genes.
Another problem concerns the coding regions of DNA themselves. In purely molecular computer analysis, the elevation of these sections to the rank of genes requires compliance with purely formal criteria: whether they contain punctuation marks necessary for reading the information, or not, i.e. whether a specific gene product is synthesized on them and what it is. At the same time, the role, time and place of action of most potential genes are still unclear. According to Venter, it may take at least a hundred years to determine the functions of all genes.
Next, it is necessary to agree on what to put into the very concept of “genome”. Often, the genome is understood only as genetic material as such, but from the standpoint of genetics and cytology, it consists not only of the structure of DNA elements, but also the nature of the connections between them, which determines how genes will work and how they will go individual development under certain environmental conditions. And finally, we cannot fail to mention the phenomenon of so-called “non-canonical heredity,” which attracted attention in connection with the “mad cow disease” epidemic. The disease began to spread in the UK in the 1980s after cows were fed processed sheep heads, which included sheep suffering from scrapie, a neurodegenerative disease. A similar disease began to be transmitted to people who ate the meat of sick cows. It was discovered that the infectious agent is not DNA or RNA, but prions (from the English prions, protein infectious particles, protein infectious particles). Penetrating into the host cell, they change the conformation of normal analogue proteins. The prion phenomenon has also been discovered in yeast.
Thus, the attempt to present genome decoding as a purely scientific and technical task is untenable. Meanwhile, this view is widely promoted even by very authoritative scientists. Yes, in the book Code codes (The Code of Codes, 1993) W. Gilbert, who discovered one of the methods of DNA sequencing, argues that determining the nucleotide sequence of all human DNA will lead to changes in our ideas about ourselves. “Three billion base pairs can be stored on a single CD. And anyone can pull out their disk from their pocket and say: “Here it is - I am!” Meanwhile, it is necessary to know not only the order of the links in the DNA chain and not only mutual arrangement genes and their functions. It is important to find out the nature of the connections between them, which determines how genes will work under specific conditions - internal and external. After all, many human diseases are caused not by defects in the genes themselves, but by violations of their coordinated actions and their regulatory systems.
Decoding the genome of humans and other organisms has not only led to progress in many areas of biology, but has also given rise to many problems. One of them is the idea of a “genetic passport”, which will indicate whether a given person carries a mutation that is dangerous to health. This information is expected to be confidential, but no one can guarantee that information will not leak. There is precedent for the "genetic testing" of African Americans to determine whether they carry the hemoglobin gene that contains a mutation associated with sickle cell anemia. This mutation is common in Africa in malarial areas, and if it is present in one allele, it provides the carrier with resistance to malaria, while those with two copies (homozygotes) die in early childhood. In 1972, as part of the fight against malaria, more than $100 million was spent on “certification”, and after the program was completed, it turned out that a) healthy people, carriers of the mutation, a guilt complex arises, these people feel not quite normal, and others begin to perceive them as such; b) new forms of segregation have appeared - refusal to hire. Currently, some insurance companies provide funds for DNA tests for a number of diseases, and if future parents, carriers of an unwanted gene, do not agree to terminate the pregnancy and they have a sick child, they may be denied social support.
Another danger is experiments in transgenosis, the creation of organisms with genes transplanted from other species, and the spread of such “chimeras” in environment. Here, the irreversibility of the process poses a particular danger. If a nuclear power plant can be closed, the use of DDT and aerosols can be stopped, then removed from biological system a new organism is impossible. Mobile genes discovered by McClintock in plants and similar plasmids of microorganisms are transmitted in nature from species to species. A gene that is harmful or beneficial (from a human point of view) for one species can, over time, pass to another species and change the nature of its action in unpredictable ways. In America, the powerful biotechnology company Monsanto has created a potato variety whose cells include a bacterial gene encoding a toxin that kills the larvae of the Colorado potato beetle. It is claimed that this protein is harmless to humans and animals, but European countries have not given permission to grow this variety in their countries. Potatoes are tested in Russia. Experiments with transgenic plants require the strictest isolation of plots with experimental plants, but in the protected fields with transgenic plants at the Institute of Phytopathology in Golitsyn, near Moscow, maintenance workers dug up potatoes and immediately ate them. In the south of France, an insect resistance gene has jumped from crops to weeds. Another example of a dangerous transgenosis is the release of salmon into Scottish lakes, which gain weight 10 times faster than regular salmon. There is a danger that these salmon will end up in the ocean and disrupt the existing population balance of other fish species.
The human genome contains approximately 38,000 genes, which represent individual units of heredity.
Germinal cell lines (sex, reproductive, germline cells) contain one copy of the genetic material and are called haploid, somatic cells (non-germ line cells) contain two complete copies and are called diploid. Genes are combined into long segments of deoxyribonucleic acid (DNA), which, during cell division, together with proteins, form compact complex structures - chromosomes. Each somatic cell has 46 chromosomes (22 pairs of autosomes, or non-sex chromosomes, and 1 pair of sex chromosomes - XY in men and XX in women). Sex cells (eggs, sperm) contain 22 autosomes, 1 sex chromosome, i.e. 23 chromosomes in total. The fusion of germ cells leads to the formation of a complete diploid set of 46 chromosomes, which is again realized in the cells of the embryo.
The human genome molecule has three structural blocks: a pentose sugar (deoxyribose), a phosphate group and four types of nitrogenous bases - purine (adenine and guanine) or pyrimidine (thymine and cytosine). These four types of bases form the alphabet of the genetic code. The main subunit of DNA is a nucleotide, consisting of a deoxyribose molecule, one phosphate group and one base. They combine in a certain sequence - adenine with thymine, cytosine with guanine. Different long sequences of nucleotide bases code for different proteins. Individual triplets correspond to transfer RNAs, each of which corresponds to a specific amino acid. Each human genome contains about 3 billion nucleotide pairs, which together encode the entire set of proteins in the human body.
Only a small portion of the cell's DNA (10% of the total DNA content) is actively functioning during the metabolically active period of the cell cycle. Some of the inactive genetic material may have important to regulate gene expression or to maintain chromosome structure and function.
Most of the human genome is contained in cell nuclei. Mitochondria ( cell organelles, producing energy) contain their own unique genome. The mitochondrial chromosome has a double-stranded circular DNA molecule, including 16,000 DNA base pairs, the sequence of which is completely deciphered. Proteins that make up mitochondria can be synthesized in the mitochondria themselves based on information contained in the mitochondrial genome, or synthesized on the basis of genetic information contained in the human nuclear genome and transported to organelles. All mitochondria are passed on from the mother (since the sperm does not usually pass on mitochondria to the fertilized egg); mitochondria with different genomes within the same cell represent different lineages of mother cells from which they originated.
Structure and function of the human genome
The main purpose of the human genome is the production of structural proteins and enzymes. This process includes a series of stages called transcription, processing and translation. To transfer information, the original DNA molecule is "unraveled" to form single-stranded DNA, with one or the other strand (or both) acting as a template for copying. If this occurs during cell replication, each DNA strand is copied to form two new double-stranded daughter DNA molecules; this process is called replication. If the process occurs during a metabolically active period of the cell cycle, only one strand of DNA is copied to form single-stranded messenger RNA (mRNA); this process is called transcription. The code for each gene is transcribed from DNA to mRNA, including the information needed to code amino acids (exons) and the non-coding nucleotide sequences located between exons (introns).
The resulting mRNA differs from DNA because it contains ribose instead of deoxyribose and the pyrimidine base uracil instead of thymine. Before leaving the nucleus, the primary mRNA transcript undergoes processing, during which non-coding intron regions are removed from the mRNA molecule, and the remaining coding regions-exons are combined into a single chain to form functional mRNA, which then migrates into the cytoplasm, where translation occurs. During translation, mRNA regulates protein production at the ribosome by forming complementary bonds between three nucleotides, called codons, and three additional nucleotides on the transfer RNA molecule, called anticodons. As the ribosome moves along the RNA from codon to codon, enzymes combine adjacent amino acids bound to tRNA molecules to form covalent peptide bonds. The structure of polypeptide chains and ultimately formed proteins is determined by the nucleotide sequences of mRNA.
“Today, ten years after the completion of the Human Genome Project, we can say: biology is much more complex than scientists previously imagined,” Erica Check Hayden writes in the March 31 issue of Nature News and the April 1 issue of Nature.1
Transcription Project human genome became one of the greatest scientific achievements of the late twentieth century. Some compare it to the Manhattan Project (US program to develop nuclear weapons) or the Apollo program (manned space flights NASA). Previously, reading sequences from DNA characters was considered a boring and painstaking job. Today, deciphering the genome is something natural. But with the emergence of new data on the genomes of a variety of organisms - from yeast to Neanderthals, it became obvious: “As sequencing and other advanced technologies provide us with new data, the complexity of biology is growing before our eyes.”, writes Hayden.
Some discoveries were surprisingly simple. Geneticists expected to find 100 thousand genes in the human genome, but it turned out to be about 21 thousand. But, to their surprise, along with them, scientists also discovered other auxiliary molecules - transcription factors, small RNAs, regulatory proteins that actively and interconnectedly act according to the scheme , which just doesn’t fit in my head. Hayden compared them to the Mandelbrot set in fractal geometry, demonstrating an even deeper level of complexity in biological systems.
"In the beginning, we thought that signaling pathways were quite simple and straightforward, says Tony Pawson, a biologist at the University of Toronto in Ontario. -Now we understand that the transfer of information in cells occurs through an entire information network, and not along simple, separate paths. This network is much more complex than we thought."
Hayden admits that the concept of "junk DNA" has been smashed to smithereens. Regarding the idea that gene regulation is a direct and linear process, i.e. genes encode regulatory proteins that control transcription, she noted: “Just ten years into the post-genomic era in biology has eliminated that notion.” "Biology's new insight into the world of non-coding DNA, once called 'junk DNA,' is both fascinating and perplexing." If this DNA is junk, then why? human body transcribes between 74% and 93% of this DNA? The abundance of small RNAs produced by these non-coding regions and the way they interact with each other came as a complete surprise to us.
Understanding all this dispels some of the initial naivety of the Decipherment Project. human genome. The researchers intended “unlock the mysteries of everything from evolution to the origin of disease”. Scientists hoped to find a cure for cancer and trace the path of evolution through the genetic code. This was the case in the 1990s. Biologist-mathematician from the University of Pennsylvania (Philadelphia) Joshua Plotkin said: “The very existence of these extraordinary regulatory proteins shows how incredibly naive our understanding of basic processes is, for example, how a cell starts and stops functioning.”. Princeton University (New Jersey) geneticist Leonid Kruglyak says: “It is naive to think that to understand any process (be it biology, weather forecasting or anything else) you just need to take a huge amount of data, run it through a data analysis program and understand what happens during the process.”.
However, some scientists still seek simplicity in complex systems. The principles of top-down analysis attempt to create models in which basic reference points fall into place.
New discipline" Systems biology" is designed to help scientists understand the complexity of existing systems. Biologists hoped that by listing all the interactions in the circuitry of the p53 protein, a cell, or between a group of cells, and then translating them into a computational model, they would be able to understand how all biological systems work.
In the tumultuous post-genomics years, systems biologists have launched a huge number of projects built on this strategy: they have attempted to create biological models of systems such as the yeast cell, E. coli, the liver, and even the “virtual human.” Currently, all of these efforts have hit the same roadblock: it is impossible to collect all the relevant information about every interaction included in the model.
The way the p53 protein works, which Hayden talks about, is wonderful example unexpected complexity. Discovered in 1979, p53 was initially considered a cancer promoter rather than a cancer suppressor. "Few other proteins have been studied more thoroughly than p53.", noted the scientist. “However, the history of the p53 protein turned out to be much more complex than we initially thought.”. She revealed some details:
“Researchers now know that p53 binds to thousands of plots DNA, and some of these sections are thousands of base pairs of other genes. This protein influences cell growth, death and structure, as well as DNA repair. It also binds to a variety of other proteins that can alter its activity, and these protein-protein interactions can be adjusted by the addition of chemical modifiers such as phosphate and methyl groups. Through a process known as alternative splicing, the p53 protein can acquire nine different forms , each of which has its own activity and chemical modifiers. Biologists now understand that the p53 protein is involved in non-cancer processes such as fertility and early life. embryonic development. By the way, it is completely illiterate to try to understand the p53 protein alone. In this regard, biologists have switched to studying the interactions of the p53 protein, as shown in the drawings with boxes, circles and arrows that symbolically depict its complex labyrinth of connections.”
Interaction theory – new paradigm, which replaced the unidirectional linear diagram"gene - RNA - protein". This scheme was previously called the “Central Dogma” of genetics. Now everything looks incredibly alive and energetic, with promoters, blockers and interactomes, chains feedback, feedforward processes and "incomprehensibly complex signal transduction pathways." “The story of the p53 protein is yet another example of how biologists' understanding is changing with the advent of genomic-era technologies.”, Hayden noted. “It expanded our understanding of known protein interactions, and broke down old ideas about signal transduction pathways in which proteins like p53 triggered a specific set of downstream sequences.”
Biologists have made a common mistake in thinking that more information will bring more understanding. Some scientists still continue to work in a “bottom-up” manner, believing that the basis of everything is simplicity, which will sooner or later be revealed. “People are used to complicating things”, noted one researcher from the city of Berkeley. At the same time, another scientist who planned to reveal the genome of the yeast fungus and its relationships by 2007, was forced to postpone his plans for several decades. It is clear that our understanding remains very superficial. Hayden concluded: "beautiful and mysterious structures biological complexity (such as we see in the Mandelbrot set) show how far they are from being solved.".
But in revealing the complexity there is also bright side. Mina Bissell, a cancer researcher at Lawrence Berkeley National Laboratory in California, admits: “Predictions that the Project deciphering the human genome will help scientists solve all the mysteries, drove me to despair.” Hayden says: “Famous people said that after this project everything will become clear to them”. But in reality, the Project only helped to understand that “Biology is a complex science, and that’s what makes it beautiful.”.
Links:
- Erica Check Hayden, "The Human Genome in Ten Years: Life Is Very Complicated," Magazine Nature 464, 664-667 (April 1, 2010) | doi:10.1038/464664a.
Who predicted complexity: Darwinians or Intelligent Design proponents? You already know the answer to this question. Darwinists have shown time and time again that they are wrong on this issue. In their opinion, life has a simple origin (Little warm pond in which Darwin's dreams float). Previously, they believed that protoplasm was simple matter, and proteins were simple structures, and genetics was a simple science (remember Darwin's pangenes?). They believed that the transfer of genetic information and DNA transcription are simple processes (Central Dogma), and that there is nothing complicated about the origin of the genetic code (the RNA world, or Crick's "frozen case" hypothesis). Comparative genomics, they believed, is a simple branch of genetics that allows us to trace the evolution of life through genes. Life, in their opinion, is a garbage dump of mutations and natural selection ( vestigial organs, junk DNA). It's simple, simple, simple. Simpletons...