Any woman who’s considered having children knows that age isn’t on her side. Growing older not only makes it harder to have a baby, but also raises the risk that a baby might be born with a genetic disorder. Now, as it turns out, it’s becoming more clear that a father’s age matters as well.

Researchers have been trying to discover why older fathers, usually men in their 50s or above, are more likely to have children with certain genetic disorders. Now, a team of researchers have found a possible reason — a link between a type of benign testicular tumor and the genes of children born to men with such tumors.

In their findings, published in a recent edition of Nature Genetics, the researchers point to a connection between these tumors and certain rare disorders in children.  The researchers also propose that these tumors might be connected to more common disorders in children as well. This type of testicular tumor becomes more common as men age, and might play a role in shaping a child’s genetic predispositions for a number of different conditions, including some that don’t arise until later in life.  (The Nature Genetics piece is heavy on numbers and short on context — you can also find a more reader-friendly article here.)

As we discuss in Chapter 3 of our book, a number of prenatal genetic tests are now available for older expectant mothers. Dads can undergo carrier testing, but other types of screening remain a ways off.