Human evolution continues

Geneticists have refuted the myth of the degradation of humanity

Alexander Khramov, Infox

Scientists have found out that natural selection still affects representatives of our species, eliminating carriers of harmful mutations, so that degradation of humanity is not threatened yet, reports Infox.

This conclusion was reached by experts from American specialists from Columbia University, whose article was published in the journal PLOS ONE.

One can hear the opinion that due to the success of healthcare, natural selection has ceased to influence humanity, thereby condemning it to slow degeneration. Carriers of harmful mutations that would have died earlier in infancy, thanks to medicine, get a chance to survive and then pass on their unhealthy genes to offspring.

The authors of the article showed that the prevalence of harmful mutations among humans remains extremely low, which means that it is too early to talk about the degradation of our species. Scientists came to this conclusion by working with two databases. One of them included information about the genomes of 60 thousand Americans of European origin, the other – about the genomes of 150 thousand Britons.

Despite all efforts, geneticists were able to identify only two mutations that would significantly reduce life expectancy and at the same time would be widespread. One of them is located in the ApoE4 gene, – women carriers of this genetic variation associated with the development of Alzheimer's disease die before they reach the age of 70.

Another mutation was detected in the CHRNA3 gene – men, its carriers, often become heavy smokers and begin to rapidly go to the next world already in middle age. But, apart from these two genetic variations, scientists have not been able to identify any other disastrous mutations among modern people that would occur quite often.

This means that natural selection continues to eliminate carriers of such mutations, even if their consequences manifest themselves only in old age, as in the case of ApoE4. "Probably, men who do not carry these mutations have more children, in addition, women and men who live longer can help with grandchildren and thereby to increase the chances of their offspring to survive," explained Molly Przeworski, co–author of the article (in the press release Humans still evolving, large-scale study of genetic data shows - VM).

Portal "Eternal youth" http://vechnayamolodost.ru  07.09.2017