Do you want healthy children? Don't put it off until tomorrow!
Children of mature fathers are susceptible to an increased number of mutations, scientists say
To date, there is no consensus on whether the late conception of children causes any negative or positive consequences for human health. Nevertheless, many biologists tend to think that the quality of "building materials" – sperm and eggs – steadily deteriorates with age.
A group of scientists led by Augustin Kong from the deCODE Institute of Genetics in Reykjavik (Iceland) provided an argument in favor of this hypothesis by comparing the number of mutations in the genomes of fathers, mothers and newborn babies in 78 Icelandic families.
Biologists collected DNA samples from parents and their child, sequenced and compared them, isolating mutations in the baby's genome that were absent from his father and mother.
On average, each child's genome contained 60 mutations that were absent from his parents. On the one hand, this confirmed the data obtained in other studies, and on the other – contradicted them. This was expressed in the fact that the number of mutations was not random – it depended on the age of the baby's father.
In particular, young twenty-year-old dads transmitted only 25 new mutations to their descendants, while babies conceived by 40-year-old men contained about 65 anomalies in their genome. At the same time, the second half of the family had virtually no effect on the genetic "health" of children – on average, mothers transmitted 15 mutations to infants, regardless of their age.
Thus, an increase in the father's age by one year is accompanied by the appearance of two new mutations in the genome of his child.
Considering that approximately 10% of such mutations negatively affect the functioning of altered genes, the sequential accumulation of anomalies in the genome over several generations can lead to serious consequences.
As scientists explain, the exceptional role of the father in the genetic health of the offspring is explained by differences in the origin of eggs and sperm. Female germ cells are formed even before the birth of their owner, and new eggs do not appear in childhood and adulthood.
On the other hand, spermatozoa are continuously updated during the cycle of spermatogenesis, the duration of which is only two months. As men age, the quality of the source material for sperm cells – spermatogony cells inside the testicles - continuously deteriorates, which may explain the increased number of mutations in the offspring of mature men.
According to scientists, their discovery indicates the need to revise some basic provisions in genomics. In particular, the rate of accumulation of mutations can no longer be considered as a kind of constant value for a particular population, without taking into account fluctuations in the average age of "fatherhood" within such groups.
Portal "Eternal youth" http://vechnayamolodost.ru23.08.2012