Your teeth may hold a Neanderthal legacy, a study reveals

While many people worry about the photogenic layout of their teeth, most likely don’t think about individual tooth shape. Well, you should – because it could be partially determined by your Neanderthal ancestors.

An international team of researchers co-led by Kaustubh Adhikari of University College London (UCL) have discovered differences in teeth between ethnicities, including an apparent characteristic determined by a gene inherited from Neanderthals. His research, published on December 12 in Current biologycould one day help diagnose and treat genetic dental conditions.

The researchers, including experts from Fudan University in China, used 3D scans of dental plaster casts to analyze the measurements of the teeth of 882 volunteers of European, Native American and African descent. They then compared these dimensions with the volunteers’ genetic data and identified 18 genome regions involved in the size and shape of different teeth. In particular, 17 of these regions were identified for the first time as connected with tooth dimensions.

“Teeth can tell us a lot about human evolution, as well-preserved ancient teeth are particularly important for archaeologists, which shed light on stages, such as when we made the transition to cooked food and the size of human teeth has begun to decrease. But little is known about the genetic basis of variation in modern human populations in tooth size and shape, in part because of challenges in measuring teeth. “, he said Adhikari in a UCL. declaration. “We have now identified numerous genes that impact the development of our teeth, some of which are responsible for the differences between ethnic groups.”

Interestingly, scientists suggest that one of the identified genes originated in Neanderthals, with whom ancient humans interbred during our relatively brief prehistoric coexistence. The genetic variant, found only in volunteers of European ancestry, was associated with thinner incisors (measured from front to back). Researchers also noted that individuals with this variant tend to have smaller teeth overall. In addition, the team found that the EDAR gene, previously linked to incisor shape in East Asian people, also affects the width of all teeth.

However, “our findings did not clarify whether the genes that identify the shape of the teeth were selected in evolution because of particular advantages for dental health, so it is possible that the genes were selected because of the ‘influences that have in other areas, with differences in the shape of the teeth that result as a secondary effect,’ explained Andrés Ruiz-Linares of UCL and Aix-Marseille University, who co-led the study. Basically, researchers are not sure why genes evolved to impact the shape of teeth in this way.

“Some of the genes that contribute to the normal variation in tooth sizes among healthy people may also contribute to pathogenic variation, such as teeth not growing in or other dental health conditions,” he said. Qing Li of Fudan University, who co-led Fudan University. to study Pathogenic variations are genetic differences that increase an individual’s chance of developing a particular disease or genetic disorder. In other words, the genes that determine the measurements of the teeth could also determine health problems.

Consequently, “we hope that our findings could be medically useful, if people with particular dental problems could undergo genetic tests to help in the diagnosis, or if some dental anomalies could be treated one day with gene therapies,” added Li.

It remains to be seen how this research could lead to practical medical applications. Meanwhile, Neanderthal teeth join a host of other features we may have inherited from our long-lost relatives, including pain tolerance and nose shapes.