According to a study led by researchers at University College London, one of these genetic variations was inherited from Neanderthals.
El Sidrón Neanderthals taste wild mushrooms, pine nuts, and forest moss. Image credit: Abel Grau, CSIC Communication.
“Teeth can tell us a lot about human evolution. Well-preserved ancient teeth are of particular interest to archaeologists, as we learned from the transition to cooked foods and when human teeth began to shrink in size.” We will highlight milestones such as when the , a researcher at University College London.
“However, little is known about the genetic basis of differences in tooth size and shape in modern humans, partly because teeth are difficult to measure.”
“We have now identified a large number of genes that influence tooth development, some of which are responsible for differences between ethnic groups.”
In the study, Dr. Adhikari and his colleagues used data from 882 Colombian volunteers of European, Native American, and African descent.
The dataset included crown measurements (dimensions of the part of the tooth visible above the gums) taken from 3D scans of dental plaster casts.
The researchers compared these measurements to participants' genetic information in genome-wide association studies, using an analytical approach called multi-omics that integrates numerous data sources.
They identified 18 genomic regions that influence the size and shape of different tooth groups, 17 of which had not previously been associated with tooth dimensions.
One of the new connections concerned genes thought to have been inherited from Neanderthals through interbreeding with ancient humans. homo sapiens.
This genetic variation, which contributes to the biological pathway of tooth development, is found only in people of European descent, and carriers of the mutation have thinner incisors (the eight teeth located at the front of the mouth). The thickness of the tooth was measured from back to front).
Generally speaking, people of European descent had smaller teeth.
Scientists also found a link between tooth dimensions and a gene already known to influence the shape of incisors in East Asians, but the new study shows that this gene, called EDAR, It turns out that it also determines the width of all teeth.
“Some of the genes that contribute to normal variations in tooth dimensions in healthy people may also contribute to pathogenic variations, such as tooth growth failure and other dental health conditions,” said a researcher at Fudan University. said researcher Dr. Chin Lee.
“We hope that our findings will have medical benefits, such as people with certain dental problems being able to undergo genetic testing to help diagnose them, and dental abnormalities one day being treated with gene therapy.” I hope.”
“Our findings did not reveal whether the genes that specify tooth shape were selected during evolution for special benefits for dental health. “Differences that occur as a side effect may have been selected for the shape of the area as well as its influence on other areas,” said Professor Andres Luis Linares, a researcher at University College London, Fudan University, and Aix-Marseille University. said.
a paper The findings were published in a magazine on December 12th. current biology.
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Chin Lee others. PITX2 Expression and Neanderthal gene introgression HS3ST3A1 Contributes to changes in tooth dimensions in modern humans. current biologypublished online on December 12, 2024. doi: 10.1016/j.cub.2024.11.027
Source: www.sci.news
