There is now proof: the number of mutations in a child’s DNA increases the older the father is at the time of conception.
The age of the father at the time the child is conceived is actually the most crucial factor for the number of mutations in the child’s DNA, while the age of the mother is of virtually no importance in this context.
This is the result of the most comprehensive analysis to date of the genome in nuclear families. Seventy-eight Icelandic children and their parents had their DNA sequenced and analysed by the Icelandic biotech firm deCODE Genetics, in collaboration with a British researcher and one from Aarhus University. The result was published in the August 2012 issue of the scientific journal Nature.