The research was a collaboration between scientists at University College London (UCL), Aix-Marseille University, France, and the Open University. It examined 59 facial parameters in a group of 6000 people in Latin America and drew links between facial geometries and genetic variations.
'The face shape genes we found may have been the product of evolution as ancient humans evolved to adapt to their environments', said Dr Kaustubh Adhikari of UCL and the Open University, and co-corresponding author of the paper. He continued: 'Possibly the version of the gene determining lip shape that was present in the Denisovans could have helped in body fat distribution to make them better suited to the cold climates of Central Asia and was passed on to modern humans when the two groups met and interbred.'
The study, published in Science Advances, is the first to reveal that a gene from an extinct type of early human, the Denisovans, has an effect on face shape in modern humans.
Part of the reason that this study was able to identify such novel components in facial development is that Latin Americans represent a more genetically diverse population comprising African, European, and Native American heritages.
Dr Pierre Faux of Aix-Marseille University and co-first author of the study explained: 'To our knowledge this is the first time that a version of a gene inherited from ancient humans is associated with a facial feature in modern humans. In this case, it was only possible because we moved beyond Eurocentric research; modern-day Europeans do not carry any DNA from the Denisovans, but Native Americans do.'
In addition to the discovery that a Denisovan gene is involved in facial development the study also highlighted the role of a gene called VPS13B known to be involved in facial structure in mice. These findings collectively demonstrate that some of the fundamental genetic bases of facial development are similar among mammals.
The VPS12B gene is also important in the genetic disorder Cohen syndrome which can cause developmental abnormalities of the face and head. The researchers hope that their findings will not only shed light on the evolution of facial structure but also offer advancement towards the understanding of genetic facial abnormalities.
Co-corresponding author Professor Andres Ruiz-Linares of UCL and Aix-Marseille University said: 'Research like this can provide basic biomedical insights and help us understand how humans evolved.'