London: Examining 3-D face models of nearly 1,000 female twins, researchers have found that the shapes of the end of the nose, the area above and below the lips, cheekbones and the inner corner of the eye are highly influenced by genetics.
“The notion that our genes control our face is self-evident. Many of us have facial traits that clearly resample those of our parents and identical twins are often indistinguishable,” said lead researcher Giovanni Montana, Professor at King’s College London.
“However, quantifying precisely which parts of the face are strongly heritable has been challenging so far,” Montana said.
For the study, published in the journal Scientific Reports, the research team took scans of twins’ faces using 3-D cameras and custom built statistical software to generate thousands of points that were perfectly aligned across the faces and then measured how ‘curved’ each face looked at each one of those locations.
The researchers then compared how similar these measurements were between identical twins, who have the same genes, and non-identical twins, who only share half of the genes.
By seeing which parts of the face are the most similar in shape in a pair of identical twins, the researchers then calculated the likelihood that the shape of that part of the face is determined by genetics.
This likelihood is quantified as the “heritability”, a number between zero and one, where a larger number implies that it is more likely that the shape of the face is controlled by genes, the researchers said.
“By combining 3D models of the face with a statistical algorithm that measures local changes in shape, we have been able to create detailed ‘face heritability maps’,” Montana said.
“These maps will help identify specific genes shaping up the human face, which may also be involved in diseases altering the face morphology,” Montana added.