Under Mendel’s laws of inheritance, you could thank mom and dad equally for all the outstanding qualities you inherited.
But there’s long been some fine print suggesting that a mother’s and father’s genes do not play exactly equal roles. Research published last month now suggests the asymmetry could be far more substantial than supposed. The asymmetry, based on a genetic mechanism called imprinting, could account for some of the differences between male and female brains and for differences in a mother’s and father’s contributions to social behavior.