Genetic differences influencing tooth shape, including a trait passed down from Neanderthals, have been uncovered by a team of researchers.
A group of researchers, including those from UCL, has identified genetic differences that shape your teeth, one of which is a gene inherited from Neanderthals.
A recent study featured in Current Biology has revealed significant variations in tooth structure across different ethnic groups, possibly linked to a Neanderthal-derived gene found solely in participants of European descent.
Dr. Kaustubh Adhikari, a co-lead author from UCL Genetics, Evolution & Environment and The Open University, commented: “Teeth provide valuable insights into human evolutionary history. Well-preserved ancient teeth are vital for archaeologists, helping us understand key developments, such as when our ancestors began cooking food and the reduction in human tooth size over time. However, the genetic factors behind variations in modern humans’ tooth size and shape have not been extensively studied, mainly because measuring teeth poses challenges.”
“Our research has now pinpointed various genes that play a role in tooth development, some of which account for differences seen among ethnic groups.”
The study analyzed data from 882 Colombian volunteers of mixed European, Native American, and African ancestry, using dental crown measurements obtained from 3D scans of dental plaster models. Researchers correlated these measurements with the volunteers’ genetic data through a genome-wide association study, utilizing a multiomics approach that integrates diverse datasets.
The international team, including researchers from UCL, the Open University, Fudan University (China), Aix-Marseille University (France), and National University of La Plata (Argentina), discovered 18 genomic regions associated with the size and shape of various teeth, with 17 of these regions previously unlinked to tooth dimensions.
Among the new findings was a gene believed to have been inherited from Neanderthals, resulting from ancient human interbreeding. This genetic variant affects a biological pathway related to tooth development and was present exclusively among individuals of European ancestry. Those carrying this variant exhibited thinner incisors (measured from the back to the front of the eight front teeth), and overall, individuals of European descent tended to have smaller teeth.
The researchers also identified associations with tooth size related to a gene, EDAR, already known to influence incisor shape in East Asian populations. This new study revealed that this gene also affects the width of all teeth.
Dr. Qing Li, the first author from Fudan University, mentioned: “Some of the genes that account for normal tooth size variation in healthy individuals may also lead to dental health issues, such as missing teeth or other conditions. We hope our research may offer medical insights, potentially allowing for genetic tests for specific dental problems or even future gene therapy treatments for certain dental anomalies.”
Co-lead author Professor Andrés Ruiz-Linares from UCL Genetics, Evolution & Environment, Fudan University, and Aix-Marseille University, noted: “Our research did not determine if the genes associated with tooth shape were advantageous for dental health and evolved as such. It’s feasible that these genes were selected for other benefits, with variations in tooth shape being a secondary effect.”
The authors have previously shown that Neanderthal-inherited genes may influence pain sensitivity and the shape of our noses.
