The search for a "gay gene" may be off-target, new research finds. Another process called epigenetics that switches genes on and off may explain why homosexuality runs in families.

Epigenetics are heritable changes caused by factors other than DNA. Instead of traits getting passed down through the genes, epigenetic change happens because of the way genes are regulated, or turned on and off.

These genetic regulators may be the reason homosexuality persists in nature despite the fact that gay people are less likely to reproduce, suggests the new study published in the journal The Quarterly Review of Biology.

"These things have evolved because they're good for the parents, but they sometimes, not [with] high frequency, but sometimes carry over" into offspring, study researcher William Rice, an evolutionary geneticist at the University of California, Santa Barbara, told LiveScience. In a male fetus, Rice and his colleagues write, an epigenetic change that benefited the mother may lead to "feminization" of sexual preference — homo- or bisexuality