One of these genetic variants was inherited from Neanderthals, according to a study led by University College London researchers.
“Teeth can tell us a great deal about human evolution, as well-preserved ancient teeth are particularly important to archaeologists, shedding light on milestones such as when we transitioned to cooked food and human tooth sizes began to shrink,” said Dr. Kaustubh Adhikari, a researcher at University College London.
“But little is known about the genetic basis of variation within the modern human population on tooth size and shape, partly due to challenges in measuring teeth.”
“We have now identified numerous genes that impact the development of our teeth, some of which are responsible for differences between ethnic groups.”
For the study, Dr. Adhikari and colleagues used data from 882 volunteers in Colombia, of mixed European, Native American and African ancestry.
The dataset included dental crown measurements — dimensions of the part of the tooth visible above the gums — derived from 3D scans of dental plaster casts.
The researchers compared these measurements with the participants’ genetic information in a genome-wide association study, using an analysis approach called multiomics that brings together numerous data sources.
They identified 18 genome regions that influence the size and shape of different groups of teeth, 17 of which had not been previously linked to tooth dimensions.
One of the novel associations was on a gene believed to be inherited from Neanderthals due to interbreeding with ancient Homo sapiens.
This genetic variant, which contributes to the biological pathway of tooth development, was only found in those of European descent, and carriers of the variant have thinner incisors (thickness of the incisors, the eight teeth situated at the front of the mouth, was measured from back to front).
On the whole, those of European descent had smaller teeth.
The scientists also found associations with…
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