Love at first sight might be genetic

By  Xiong Tong 

In experiments involving fruit flies (which may have implications for humans), a team of scientists from the United States and Australia discovered that at the genetic level, some males and females are more compatible than others, and that this compatibility plays an important role in mate selection, mating outcomes, and future reproductive behaviors. 

The research team found that before mating, females experience what amounts to "genetic priming," making them more likely to mate with certain males over others.

"Our research helps to shed light on the complex biochemistry involved in mate selection and reproduction," Mariana Wolfner, professor of developmental biology at Cornell University and the senior scientist involved in the study, said. "These findings may lead to ways to curb unwanted insect populations by activating or deactivating genes that play a role in female mating decisions," she said.

To reach their conclusions, scientists mated two different strains of fruit fly females to males either from their own strainer to males from another strain.

They noted the males with which females of each strain tended to mate and then examined whether the females showed differences in behavior soon after mating and in reproduction-related activities, such as how many offspring were produced and how much sperm was stored. They also examined the females' RNA (a type of molecule) to compare the genes expressed in females mated to males of different strains.

They found that despite observed differences in mating behaviors and reproduction activities in females mated to different strains of males, there were only negligible mating-dependent differences in gene expression between the groups. This suggests that genetic changes involved in mate choice and reproduction were in place before mating began.

"It appears that females really do care about the character of their consorts," Mark Johnston, editor-in-chief of Genetics, said. "But they may not have as much control over our choice of mates as they would like to think."