It's clear that genes play a significant role in shaping the human face — just look at your biological parents or children. But scientists are just starting to figure out which genes determine the arch of your brow bone, or the point of your chin.
"The face is very complex, just like the brain is very complex," said University of Pittsburgh anthropologist Seth Weinberg, who contributed to the research.
To uncover which genes are most important in creating the face, Weinberg said scientists needed to pinpoint what traits to measure. In previous studies, researchers selected the features, but this time Weinberg and his collaborators let a computer decide via an algorithm designed by lead author Peter Claes, a research scientist at KU Leuven, in Belgium.
“We know that the face has a lot of interrelationships between the parts,” he said. “What we’re doing is simply allowing the data to tell us which parts tend to hang together the most.”
After looking at three-dimensional images of more than 4,000 faces, the program helped researchers find 15 genetic markers — out of likely thousands — that contribute to facial morphology. Future work could build on this knowledge to understand conditions like cleft lips and palates.
“There’s a huge amount of variability that you see when people walk into the clinic. I mean you’ve got people with very, very mild forms. And very, very severe forms. And we have no understanding of why that’s the case,” he said.
The study mostly looked at faces of European descent. Weinberg said broadening the sample might reveal differences between ethnicities in genetic variation for facial morphology.
The study was published online this month by the journal of Nature Genetics.