Skip to main content
Premium Trial:

Request an Annual Quote

Researchers Uncover Three Variants That Influence Human Facial Features

NEW YORK (GenomeWeb) – Researchers have uncovered three genetic variants that influence how someone looks.

Facial features tend to run in families, suggesting that genes govern much of how people look. Researchers led by the University of Oxford's Walter Bodmer analyzed images of nearly 3,500people from the People of the British Isles study, the TwinsUK cohort, and a group of East Asian volunteers to find facial features that were highly heritable. They then conducted genome-wide association studies of these features to uncover three genetic variants that affect a person's facial features. The work was published this week in the Proceedings of the National Academy of Sciences.

"[W]e have identified three specific genetic variants with notable effects on facial profiles and eyes," Bodmer and his colleagues wrote in their paper.

He and his colleagues first analyzed images of 1,832 people from the People of the British Isles study, 1,567 people from the TwinsUK cohort, and 33 people of East Asian ancestry. These images were then transformed into a series of nearly 30,000 surface points that were analyzed in comparison to a generic model face.

By drawing on a concept from animal breeders, the researchers determined the additive genetic value (AGV) for each of these surface points. They calculated that the mean heritability of the AGVs for the eyes was 76.1 percent and 81.5 percent for the profile.

After carrying out principal components analyses of the AGVs for the eyes and profiles for the combined cohort, Bodmer and his colleagues selected five axes for genetic association analyses for each of the facial regions.

The discovery phase of the GWAS relied on the People of the British Isles dataset, for which 1,423 had both good-quality facial imaging and genotypes. The researchers compared the people who fell in the upper or lower extremes based on their principal components scores against those in the middle and those who had not been phenotyped. They also compared the group as a whole as well as women only. From this, the researchers uncovered 17 SNPs for profile features and 12 SNPs for the eyes that they took forward for replication.

Three of those SNPs were replicated within the TwinsUK cohort: rs2045145 in PCDH15, rs11642644 in MBTPS1, and rs7560738 in TMEM163. The rs2045145 SNP is located in a PCDH15 intron, a gene in which recessive variants cause a form of Usher syndrome, which is marked by hearing and balance difficulties, though occasionally also morphological changes.

At the same time, rs11642644 falls within an exon of MBTPS1, which cleaves SREP proteins, which have been implicated in conditions like Smith-Magenis and Potocki-Lupski syndromes. Both of those conditions have associated facial dysmorphias.

Lastly, rs7560738 is located in TMEM163, a highly conserved gene that binds MCOLN1. Mutations in MCOLN1 cause mucolipidosis, and while that condition isn't known for affecting facial features, a few cases of facial dysmorphia have been reported.

The researchers noted that their study was limited by its sample size and limited ethnic diversity.

Bodmer and his colleagues said there are likely more variants to be uncovered. "We suggest that many more specific and relatively large genetic variant effects on human facial features will be found in the future using approaches such as we have described," the researchers wrote in their paper.