An international team of biologists examined data on age-related epigenetic marks in mammals' sperms and their effects on offspring, and a study showed that male sex cells are undergoing changes that may affect the health of late children.
In contrast to women, men can maintain fertility, i.e. the ability to conceive, until the very age of old age; in recent decades, the number of couples who marry and have children at a mature age has increased; this process has not gone unnoticed by science, but most studies focus on the health effects of the mother's age.
Researchers from the MGU, together with American colleagues from the University of Massachusetts in Amherst and the Medical Faculty of the State University of Wayne, decided to correct this deficiency and analysed research into the age changes in male sex cells.
Spermatosoids are formed over a lifetime in the process of dividing semenatogenics, sexual cells of the predecessors. In dividing a cell, DNA copying can occur with errors -- that's how mutations occur. The division occurs on average once every 16 days. This means that there are about 23 such divisions in a year. As the cells that preceded the sperms are increasingly divided, more and more are accumulated, and the errors in their DNA are observed by scientists.
But changes in the sexual cell genome can be caused not only by mutations, but also by epigenetic events, which are processes that do not affect the sequence of DNA, but can include, turn off the genes or change their mode of operation.
Most often, researchers observe cytosine methylation: a group of one carbon atom and three hydrogen atoms joining the DNA base; in various studies, scientists have found that, with the age of sperm in DNA, methylation changes in genes related to early foetal development and psychoneurological disorders.
Researchers believe that such changes can be transmitted to the offspring and have an impact on their development, and researchers believe that in-depth study of these processes will help to find ways to reverse the epigenetic clock and restore the reproductive health of men.