Comprehensive coverage

The mapping of the human genome has been completed, humans are identical in 99.9 percent of their genes.

Scientists today published the first detailed analysis of the human genome

The decoding of the genome is complete: humans are identical in 99.9% of the genetic material

All the instructions needed to create a human are written on an incredibly small number of genes - only twice the number needed to create a worm or a fly. This is according to the first detailed analysis of the complete human genome, published yesterday in the "Washington Post". The publication also shows that hundreds of these genes originate from bacteria that penetrated the bodies of ancient humans millions of years ago, and left the remains of their DNA in the human genetic material.

However, the most impressive finding, according to the researchers, is how little of the human genome - which consists of 23 pairs of chromosomes that contain the master plan for human life - is directly dedicated to the creation of humans, and how much other biological activity, unrelated to human function, occurs in different regions of the genome .

According to the findings, the genetic instructions for making a person are found in less than three centimeters of the DNA coil - the hereditary molecule made in the form of a double helix - which is two meters long. This coil is packed into almost every cell in the body. The rest of the genome is full of strange life-like entities that have invaded and settled within the genome, including microscopic pieces of foreign DNA that feed, like parasites, on human DNA, and even smaller pieces that feed on these parasites.

Although researchers knew that such creatures exist in the human genome, only now have they been able to understand how common they are, how they are distributed among the genes, and how these complex communities have evolved over millions of years inside human cells. The new findings show that the human genome is much more than a sequence of biological markers written on a coiled coil of DNA. It is a vibrant and dynamic ecological environment - a world full of tiny creatures.

Today, scientists are expected to describe the latest research results at a press conference that will be held in Washington, and will be transmitted via the Internet to the rest of the world.

The researchers, who filtered the genetic material using computerized search engines, discovered more than 40 genes that cause diseases, which were not known until now. These genes cause different types of epilepsy, deafness, color blindness and muscular dystrophy. Hundreds of other genes are expected to be discovered in the coming years, and their discovery will accelerate the development of new drugs and diagnostic tests.

Other areas of the genome are actually genetic "wildernesses", where the eye does not come across a single gene related to human function. However, there is life there. Similar to genes, the creatures living in these areas of the human genome are also composed of DNA. But they do not contain coded messages for the production of any substance that is useful for the human body.

Most of these entities are able to survive and reproduce within the human genome, but they are so dependent on the genome that they cannot leave it. Other entities are actually remnants of genes left behind by prehistoric viruses. These remains have been inherited from one human generation to the next, while they gradually degenerate.

Now the geneticists are extending and analyzing the genetic remains, some of which exist in this human and pre-human genetic material for more than 500 million years. Through these studies, the geneticists learn how genetic innovations during evolution led to the breakthroughs that allowed early vertebrates to develop into humans.

Thousands of researchers are involved in the international genome project. In the US, it was chaired by the National Institutes of Health and the Ministry of Energy, together with the private company Celera Genomics. At a celebratory event at the White House in June 2000, the heads of the two teams - the public and the private - announced that each of them had discovered, separately, the order of almost all three billion "letters" of the biochemical code that makes up the genome.

The research answers age-old questions, including why the human sense of smell is so crude compared to other mammals. In the last 10 million years, it turns out, the creatures that preceded man lost more than half of the thousand genes related to smell that their ancestors had, probably to concentrate on vision and other senses.

The research also raises new and difficult questions: for example, how is it possible that humans - for all their passions, fears, abilities to create art, music, culture and war - are the way they are thanks to only 30 thousand genes, only five times the number of genes in baking yeast.

Although this sounds paradoxical, the complexity of the genome is actually related to the fact that humans have few genes. The estimate of 30 thousand, in which the two teams were quoted, is a rough estimate. It is difficult to identify actual genes in the material that makes up the genome, and their number may increase by several thousand as the search continues. But the final number will be much smaller than previous estimates, which only a year ago had about 80 thousand gardens.

This assessment raises the question of how 30 thousand "sentences" of coded instructions can order the production of hundreds of thousands of components, which together form a human body. The main answer, according to scientists, is that the approximately 30 substances (mainly proteins), which are produced by the 30 human genes, are cut into smaller pieces after their formation, and then these pieces change places and are glued together in new connections.

Just as many different sentences can be assembled from a limited number of words, so ten or more different proteins can be produced from the instructions within one given gene. In contrast, single genes in simple organisms, such as flies and worms, usually produce one protein.

The comparison of the human genome with the genomes of simpler creatures has shown researchers in unprecedented detail how some genetic innovations helped early vertebrates evolve. In one case, some genes, which seem to have helped flies and worms fight against invading bacteria, replicated themselves and rearranged themselves within the genetic material of vertebrates - which were in the midst of an evolutionary process, which eventually led to the creation of the human species - until they became the cluster of genes that encode the human immune system.

But despite the evolutionary creativity that gave birth to the human race, the diversity between man and man is astonishingly limited. Humans are identical to each other in about 99.9% of their genetic material. This indicates the short time that has passed since the human race was created, and the little time it had available to diversify.

Many questions remain unsolved. One is why some genetic parasites die out, while others thrive. Entire cultures seem to have risen and fallen within the human genome, and continue to do so. "It's a humbling perspective," said Robert Waterston, director of the Genome Center at the University of Washington. According to him, a person who studies the human genome feels that he is no longer the center of attention; Man is no longer the cause and purpose of everything.

The origin of the mutations is in men

One of the results of genome research may fuel the gender wars: the finding that sperm cells are the primary source of genetic mutations in humans. Hence, men are the main source of genetic errors in offspring, but also a main source of evolutionary innovation.

Researchers aren't sure why sperm cells are so loaded with genetic errors. It is possible that the process of making sperm cells involves many cell divisions, while egg cells are formed as a result of only one division. With each cell division, chromosomes are given a new opportunity to break or mutate.

The researchers struggled to determine whether the men should be blamed or praised for their multi-mutated sperm cells. The mutations usually cause damage, and in the best case they have no effect. In any case, it is the males that cause widespread molecular riots. On the other hand, different species depend on mutations to develop and renew themselves evolutionarily, so males can be seen as the great innovators of the human race.

The main points of the study

* All the instructions needed to create a human being are written on a limited number of genes

* The origin of hundreds of genes in bacteria that penetrated the bodies of ancient humans

* The instructions for making a human are found less than three centimeters from the DNA coil

* The genome is full of entities that have infiltrated it, and in them are bits of foreign DNA

* More than 40 genes have been discovered, which cause diseases such as epilepsy and deafness'
{Appeared in Haaretz newspaper, 12/2/2001}

Development of genetic medicines

With the revelation of the two destructions of the "architectural plans" of the human genetic sequence, today the signal was given for the start of the race of researchers, biochemists and pharmaceuticals people to develop medicines based on them. This is one complete map of the global human genome, published by the two bodies that mapped the database, which is defined as "the set of instructions for creating a complete person". This is of course the global human genome mapping project (HGP), which operated under the American National Institutes of Health (NIH), and the American commercial company Celera Genomics (CRA).
The two entities announced the complete map (for each company and its version) at a press conference held in Washington. The findings of the global project will be published in the British magazine "Nature", while Celera's findings will be published in the competing American magazine, "Science".

The publication of the complete genome map is a complementary step to the announcement of June 2000, when the two bodies presented the "draft" of the human genome map. Now the work of collecting the data of the human genetic code has been completed - 3 billion "letters", which represent sequences of chemical bases, and encode the basic information of the construction of the human body and its activity. The complete number of genes mapped by each body is not given precisely, but it is known that the human genome contains only about 40-30 thousand genes (as opposed to previous estimates that spoke of 100-60 thousand genes).

The publication of the data should form a basis for disease research and the development of new drugs on a genetic basis. After the publication of the complete human genome map, additional research steps are still necessary: ​​determining the role of each gene and the effects of its mutations, locating tiny variations in it (SNPs) as well as determining the protein processes.

The information collected as part of the global project is accessible to the public for free, and is streamed every 24 hours through GenBank, the project's online database. Celera, which plans to profit from the findings, markets more processed data, which it claims is more useful.

Scientists presented today (Monday 12/02/2001) a historic landmark at a press conference in Washington, where they published the results of the first detailed analysis performed on the complete human genome, whose mapping was completed last year. The findings should be a revolution in understanding the origin of diseases and their treatment.

Dr. Francis Collins from the National Human Genome Research Institute in Washington said that the study is unusual in its discoveries and the speed with which the scientists revealed at least part of the secret of genetics. "These discoveries are ahead of their time about five years earlier than expected, and here we are," he said.

The new findings show that despite the evolutionary creativity that gave birth to the human race, the diversity between humans is extremely limited. Humans from all over the world are identical to each other in about 99.9% of their genetic material. This indicates the short time that has passed since the human race was created, and the little time it had available to diversify.

Furthermore, all the instructions needed to create a human are written on an incredibly small number of genes - only twice the number of genes needed to create a worm or a fly.

It was also found that the origin of hundreds of these genes is from bacteria that penetrated the bodies of ancient humans millions of years ago, and left the remains of their DNA in the human genetic material.
"We called the human genome 'the book of life,' but in fact it is three books," said Collins, director of the National Human Genome Research Institute, in Bethesda, and one of the senior scientists in the International Human Genome Project. "This is a history book, but also a parts list with operating instructions and the most detailed medical manual ever written."

According to the new findings, the genetic instructions for making a person are found in less than three centimeters of the DNA coil - the hereditary molecule made in the form of a double helix - which is two meters long. This coil is packed into almost every cell in the body. The rest of the human genome is full of strange life-like entities that have invaded and settled within the genome, including microscopic pieces of foreign DNA that feed, like parasites, on the human DNA, and even smaller pieces that feed on these parasites.

The genome researchers, who filtered the human genetic material using computerized search engines, discovered more than 40 genes that cause diseases, which were not known until now. These genes cause different types of epilepsy, deafness, color blindness and muscular dystrophy. Hundreds of other genes are expected to be discovered in the coming years, and their discovery will accelerate the development of new drugs and diagnostic tests.

The research answers some age-old questions, including why the human sense of smell is so crude compared to other mammals. In the last 10 million years, it turns out, the creatures that preceded man lost more than half of the thousand genes related to smell that their ancestors had, probably to concentrate on vision and other senses.

Comments

  1. Interesting, amazing!
    Written in clear language and language equal to every soul.
    Thank you very much, Ronit.

Leave a Reply

Email will not be published. Required fields are marked *

This site uses Akismat to prevent spam messages. Click here to learn how your response data is processed.

Science website logo
Search