Researchers have discovered that an individual’s sex determines where in the genome are genes that affect perceived facial attractiveness.

In women, genetic variations related to beauty also appeared to be associated with body mass. But in men, these variations are linked to genes affecting blood cholesterol levels, specifically blood lipids, according to research led by Qiongshi Lu, PhD, assistant professor of biostatistics and medical informatics at the University of Wisconsin School of Medicine and Public Health.

“Interestingly, sex-specific genetic architecture of facial attractiveness was a recurrent pattern observed in almost all our analyses,” Lu said. “Our results provided new insights into the genetic basis of facial attractiveness and have broad implications for the complex relationships between perceived attractiveness and various human traits.”

The research was recently featured in the journal PLOS Genetics.

The research team identified genetic associations for attractiveness by performing a genome-wide association study using genetic information from more than 4,300 people and their perceived- attractiveness ratings based on high school yearbook photos from UW-Madison’s Wisconsin Longitudinal Study, according to the Lu study.

Facial attractiveness was measured based on each individual’s 1957 high school yearbook photo. Using an 11-point rating scale, a group of six women and six men ranked each photo from “not at all attractive” (1) to “extremely attractive” (11). The study did not highlight specific facial features such as facial shape or symmetry.

The Wisconsin Longitudinal Study is a long-term study of a random sample of men and women who graduated from Wisconsin high schools in 1957.

Lu’s research is an early step in understanding the genetic basis of human beauty, as it was based on a homogeneous group of people who are generally the same age and ethnicity. More diverse, larger studies will be needed to better comprehend the genetic architecture of facial beauty, the research suggests.

“We have little doubt that robust and comprehensive phenotypic measurements, coupled with larger sample sizes from diverse populations, will further advance our understanding of this interesting human trait,” he said.