American scientists estimate the number of mutations in the germ cells 61 pairs of parents, based on the genome of their children. They found that the number of these mutations correlates with the lifespan of the parents, their fertility and the risk of developing diseases. In addition, the researchers determined the age at which presumably mutations in the germ cells start to appear — it was the age of puberty. Work published in the journal Scientific Reports.
The accumulation of mutations in body cells — one of the most famous signs of aging, and theory, which considers it the cause of the deterioration of the body, is one of the oldest. Moreover, it is known that many diseases of accelerated aging (e.g. Werner’s syndrome) are associated with defects of DNA repair and, therefore, are accompanied by an increase in the number of mutations. However, until now the number of mutations in DNA from different cells is not used as a marker of biological age, that is a relative measure of the age of the person.
Perhaps the fact that mutations accumulate in different cells at different rates — for example, in the neural tissue essential part occurs before birth, when cells divide more actively than in adult life. Or that the number of mutations is long and expensive to measure. Besides, not all emerging pathogenic mutation or accelerate aging — the majority of them are neutral and do not affect neither the structure nor the operation of cellular proteins.
Richard cawton (Richard Cawthon) from the University of Utah along with colleagues proposed a new approach to the problem is to estimate the biological age the number of mutations in the germ cells. But since to do this directly is quite difficult, especially if we are talking about women, the researchers have used an indirect method, calculated the number of mutations that were inherited by their children.
For this they turned to the Center for the study of human polymorphisms in Utah, where 61 selected three of the two parents and the child. DNA of blood cells of all subjects were sent for whole genome sequencing, then estimated the number of new mutations in the germ line, that is, those who inherited a child. It turned out that such mutations is greater the older the parents were at the time of his birth, and fathers more than the mothers (which, in General, it is not surprising, because eggs, unlike sperm, with age, hoarding chromosomal rearrangements rather than point mutations).