Nearly 800 children are born in the U.S. each year with genetic diseases caused by mutations in a type of DNA inherited directly from their mothers. Scientists are working to prevent these diseases by helping couples have babies with DNA from three parents instead of the usual two.
A new study identifies some of the reasons why this fledgling technique might go awry — and suggests ways for fertility specialists to minimize the risk.
The diseases in question stem from problems in what’s called mitochondrial DNA. This is a collection of 37 genes that control the structures that provide energy to cells. Certain errors in these genes can