The opinion is that in the genome of each modern person there are up to 4% of genes inherited from Neanderthals. We decided to check if such a point of view is confirmed by scientific data.

The fact that modern people received 4% of genes from Neanderthals, specialists in bioinformatics They tell In an interview, and the authors of popular science articles assurethat it was these genes that made part of the sapiens fair -skinned. Used This information is in the advertisement of genetic tests. Many assurethat Neanderthal genes affect the appearance of a person and his predisposition to diseases, and some StudyWho has more these genes - Asians or Europeans.

The genome of modern man by 99% coincides with chimpanzees, and by 60% - with bananaTherefore, it would be strange if with such a close relative as Neanderthals, Homo sapiens had only 4% of the total genes. In this case, it would turn out that a person looks more like a banana than a Neanderthal. However, simple observations show that this is not so.

DNA is Macromoleculethat ensures the implementation, transmission from generation to generation and storage of the body of the body. DNA can be compared with the culinary book - it encoded information which “ingredients” to take, in what sequence to be placed and what will turn out in the end. All living creatures on the planet are protein organisms, and they consist of approximately the same set of proteins that can be located in different sequences and perform different functions. All living on the planet has A common ancestor who lived more than 3.8 billion years ago and was a primitive unicellular organism. Scientists call him the last universal common ancestor (Last Universal Common Ancestor, Luca). Since plants, animals and other organisms received the basis of their DNA from it, it is not surprising that all protein creatures are somewhat similar.

And if the last universal total ancestor lived almost 4 billion years ago, then Neanderthals (Homo Neanderthalensis) Gone Only 30,000 years ago. From a modern person of them Distinguished The almost complete absence of the chin ledge, the massive oversonal arcs that formed the undergraduate roller, the larger cranial box, low growth and more massive physique. Neanderthals used simple tools, used fire, ate mainly meat food and,, likelyThey even had their own language.

Scientists have no consensus on how Neanderthals disappeared. One They saythat they died out, others believe that assimilated, that is, literally dissolved in another population - Homo sapiens. Neanderthal Exactly Not a direct ancestor of a modern person, most likely, in a sense, they are “brothers”-their common ancestor could be or Homo Antecessor (predecessor), or Homo Heidelbergensis (Headelberg man who received his name from Geydelberg Grotto in Germany, where in 1907 the jaw of a representative of this species was discovered). Archaeological finds indicate that Neanderthals could share the habitat with both Homo sapiens and with other subspecies of people - Denisovites And Cro -Magnons. The remains of hybrids were also found - for example, womenwho died about 90,000 years ago and was the daughter of Neanderthals and Denisovts. Exist Also the remains of Neanderthal hybrids and Homo sapiens.

Homo Heidelbergensis. The reconstruction was made by Oleg Osipov in collaboration with Svetlana Schneator for the portal "Anthropogenesis.ru"

Study, which formed the basis of the belief of 4% of Neanderthal genes in modern man, was held by a group of several dozen scientists who published the results of their work in 2010. An important role in this study was played by a Swedish biologist, one of the founders of the Paleogenetics of Svante Pebu. It is he who FoundedWhy Denisovites are a new subspecies of people, and not representatives of the already known, and also the first to completely decipher the Neanderthal genome. For research in the field of human evolution in 2022 PEBU received Nobel Prize in Physiology and Medicine.

The key for this study is the concept of SNiP (SNP), it is also one -okleotide polymorphism. DNA consists of approximately 3 billion pairs of nucleotides located in a certain order. In turn, SNiP is a DNA section on which in two organisms the sequence of nucleotides varies. For example, in humans in the General of Y, the nuclein bases of adenine (a) and thyme (t) are found, but there may be combinations with guanine (G) and cytosine (C). Accordingly, there are three options in this position in this position, or SNiP: A-T, A-G, A-C.

In theory, a person has a number of SNIPs is 36 billion (one of the 12 pairs of nuclein bases can be in each position), however, the number described so far. For example, the international project "A Thousand Genomas", cataloging genetic variations of a person, Described 84.7 million SNiPs. And the US National Medical Library Evaluates The number of SNiPs in a human population of more than 600 million. Since on average such replacements occur in about one of the 1000 nucleotides, it can be assumed that in the genome of each accidentally selected person from 4 to 5 million SNiPs.

These one -okleotide polymorphisms determine not only external differences between people, but also affect other genetic parameters - for example, hereditary diseases or, conversely, genetic resistance to some pathologies.

Scientists took three Neanderthal DNAs for comparing SNiPs: from two individuals from the Windows cave in Croatia and from one - from the Mizma cave in the Krasnodar Territory of the Russian Federation, as well as five modern human - Bushmen from South Africa, Yoruba from West Africa, Papuaus from Papua - New Guinea, Han from China and Frenchman. The choice of just such human DNA was not accidental: Neanderthals Inhabited Europe, some areas of Asia (the remains were discovered in Altai and in Uzbekistan) and the Middle East. From Asia in the future, already homo sapiens Migrated To America and Oceania, carrying with it the very non -anderthal mutations. The population of Subsakhara Africa did not intersect with Neanderthals and could receive their genes only through crossing with the descendants of Neanderthals and people from other regions.

The diagram shows how evolution was happening: an unknown common ancestor is divided into a modern person and Neanderthal, later some of the people migrate from Africa to Europe and cross there with Neanderthals, and also populate Asia, America and Oceania. Source

To analyze SNiPs, scientists also needed an additional sample. Since the last common ancestor of a person and Neanderthal is unknown, a chimpanzee was used in this capacity, with which the genomes of a modern person and Neanderthal are similar by 99%.

As a result of DNA comparison, scientists calculated the SNiPs, which in some samples coincided with the chimpanzees, that is, they were ancestral and did not change since then, while others were different, that is, they were derived and arose somewhere on the evolutionary line after both species were separated from the chimpanzees. The presence of the same derivative of SNiP in both the Neanderthal and modern man indicated that one of them acquired this mutation and conveyed as a result of crossing to another. The likelihood that the mutation, that is, the replacement of nucleotide with one of the 3 billion positions in DNA, occurred at the same time both with Neanderthal and Homo Sapiens is so small that the researchers neglected it. Since Neanderthals lived and crossed with those representatives of Homo sapiens who lived in Europe and then settled in Asia, America and Oceania, but did not contact the Africans, the scientists introduced an additional division of all human DNA into African and non -African. It turned out to identify all the derivatives of the SNiPs in the genomes of Neanderthals and Homo sapiens - there were a little more than 200,000, that is, 0.007% of the total genome. Of these, 95,000 were derived among Neanderthals and Africans, but by the ancestors of the Neprikans, and 105,000 were derivatives of Neanderthals and Neapharikans, but ancestors from the Africans. That is, 105,000 mutations by a man and Neanderthal acquired during crossing with each other, and another 95,000 arose somewhere on the evolutionary line after separation from chimpanzees, but before the division into homo sapiens and Homo Neanderthalensis, since the Africans and Neanderthals, judging by the existing archaeological data, did not contact and did not contact and did not contact They could not cross. The difference between these groups in DNA studied was 10 thousand - or 5% of 200,000 analyzed SNiPs. Given the amendments to some additional factors, scientists even say that this figure can be from 1% to 4%. If we recall that these 200 thousand SNiPs are only 0.007% of the total genome, it will become clear that it is not about 5% of Neanderthal genes, but about 0,0003% of the genome - areas that are equally different from the chimpanzes and the Sapiens and Neanderthals. By 99.7% DNA of modern people and Neanderthals coincidesas it was inherited from the general, but still unknown to science, ancestor.

Now PEBU, one of the key authors of this study, is studying how these mutations that distinguish people from Neanderthals affect the functioning of the human body. Earlier in work 2014 “Human condition is a molecular approach”, the Paleogenetic came to the conclusion that most of these SNiPs are associated with the development of the brain.

Thus, the statement that a modern person has up to 4% of the Neanderthal genes arose from improper reading of a scientific article. Homo sapiens is much closer to this disappeared type, whose DNA coincides with the human by about 99.7%. In an erroneously interpreted study, it was exclusively about those mutations that occurred after the general ancestor of the Neanderthal and man, which was still unknown to science, was evolutionarily separated from the chimpanzees. There are just 1-4% of the analyzed mutations.

Image on the cover: athree23, CC0, Via Wikimedia Commons