Researchers from the University of Utah found that differences in the rate of accumulation of mutations in healthy young people can help to predict the life expectancy of both sexes, and how long a woman is fertile. Article about the discovery is published in the journal Scientific Reports.
Scientists have long known that the body is constantly occurring DNA damage. Typically, different mechanisms to restore the damage and prevent potentially harmful mutations. However, with age, these mechanisms become less effective and in the body accumulates more mutations. Elderly parents, for example, tend to pass on more genetic mutations than younger parents.
However, the authors of the new study suggested that these mutations can be a biomarker for the rate of aging and potentially predict life expectancy in younger people, and also fertility in women.
To test this hypothesis, the researchers sequenced the DNA of 61 men and 61 women who were grandparents in 41 family of three generations. The researchers analyzed the DNA sequence of blood in the triples consisting of pairs of grandfathers and grandmothers of the first generation and one of their children of the second generation. Then a mutation detected in DNA from blood of the child, but not present in the DNA of any one of the parents, scientists have identified and investigated more thoroughly. The researchers were able to determine what the parent has occurred each mutation of the embryo, and hence the number of mutations that each parent has accumulated in the oocyte or the sperm to conception of the child.
This allowed the researchers to compare each parent and first generation with other members of the same sex and to assess their rate of aging. Scientists have discovered that the rate of mutations began to increase during or shortly after puberty. This means that aging begins in adolescence.
Some young adults have gained mutation speeds up to three times more than others. After correction of age, the researchers found that people with the slow rate of accumulation of mutations are likely to live about five years longer than those who accumulate mutations faster. This difference is comparable with the effects of Smoking or lack of physical activity. Women with the highest rates of mutations had significantly more stillborn children and miscarriages than women with fewer mutations. This suggests that the high rate of mutations affect their fertility.