In his right mind and sober memory
Scientists have discovered the genetic roots of intellectual longevity
Australian and British biologists during the experiment came to the conclusion that the rate of decline in the intellectual abilities of people in old age by 24% is due to a variety of genetic factors that manifest themselves in the form of small differences in the structure of the genome, according to an article published in the journal Nature (Deary et al., Genetic contributions to stability and change in intelligence from childhood to old age; a short retelling published in Nature News: Life-long intelligence in the genes – VM.)
It is believed that a person's intellectual abilities are laid down in early childhood and change little throughout his life until old age. This is confirmed by numerous variants of IQ tests and other psychological experiments. On the other hand, the rate of brain aging can vary greatly among different people – some elderly people quickly lose their abilities, while others retain their sharpness of mind until the last moments of life.
A group of biologists led by Ian Deary from the University of Edinburgh (UK) took the first step towards discovering the genetic secrets of intellectual longevity by comparing small differences in the structure of DNA, the so-called single nucleotide polymorphisms, with the difference in the level of intelligence of the same people in childhood and old age.
In their work, the scientists used the archives that were collected by the social services of the city of Aberdeen and the Lothian region in the first half of the 20th century. These archives contain copies of the general intelligence tests that the inhabitants of Scotland took at the age of 11 and in old age. Biologists selected two groups of Scots born in 1921 and 1936, studied the results of testing their intellectual abilities and found living representatives of these groups.
Diri and his colleagues took blood samples from their wards, extracted genetic material from them and sequenced DNA. For the purity of the experiment, biologists screened out all people with at least distant family ties at the genetic level. Having cleared the initial data, the authors of the article processed virtual DNA chains using a special computer program that compared them with each other by 500 thousand single-nucleotide polymorphisms existing in the human genome.
The researchers then compared the results with the intellectual longevity of each Scot among their wards. It turned out that genetic factors play a huge role in the aging process of the brain – according to scientists, mutations in the genome caused at least a quarter of cases – 24% – accelerated or delayed decline in the level of intelligence. In other words, descendants and close relatives of elderly people with a sharp mind will have the same distinctive feature with a 24% probability.
Thus, scientists were able to prove that small differences in the structure of the genome directly affect the rate at which a person's intellectual abilities fall in old age. Diri and his colleagues believe that an increase in the number of participants in such experiments and a more detailed study of individual variable DNA sites will clarify their conclusions.
Portal "Eternal youth" http://vechnayamolodost.ru
19.01.2012