If you tend to put off today what you can do tomorrow, you might want to rethink that strategy when it comes to having kids. A study in Iceland found that children of older fathers had more genetic mutations.
In fact, 97 percent of these mutations came from older fathers. The risk was directly related to the age of the father—a 36-year-old man would pass on twice as many mutations as a twenty year old, with even more mutations from a 70-year-old.
Unlike women, who are born with a fixed number of egg cells, men continually produce sperm throughout their lifetime. As men age, the number of errors in the DNA in their sperm increases. These mutations can then be passed onto their children.
Not all of these genetic changes are harmful, but researchers identified several that were linked to diseases like autism and schizophrenia. The results of this study, published in the journal Nature, matches previous research that found that the chance of a child being diagnosed with autism increases with the father’s age.
Diseases like autism and schizophrenia, however, are fairly uncommon in the population. So, even with a doubled risk of having a mutation, the chances of passing it onto a child is still pretty low.
One researcher, though, suggested that men could freeze their sperm when they were young if they planned on having kids later in life. It may be too soon to know whether this will be worthwhile, but it’s something to think about the next time you are getting ice from the freezer.