Your teeth may hold Neanderthal heritage, research suggests

Although many people are concerned about the photogenic structure of their teeth, they often do not think about the individual tooth shape. Well, you should, because it can be partially determined by your Neanderthal ancestry.

An international team of researchers led by Kaustubh Adhikari from University College London (UCL) has discovered dental differences between ethnic groups, including a visible feature determined by a gene inherited from Neanderthals. Their research, has been published on December 12 Current Biologymay one day help diagnose and treat genetic dental diseases.

Researchers, including experts from China’s Fudan University, used a 3D scanner of dental casts to analyze the tooth dimensions of 882 volunteers of European, Native American and African descent. They then compared these measurements with the volunteers’ genetic data and identified 18 genomic regions associated with different tooth sizes and shapes. It should be noted that 17 of these regions were identified for the first time based on tooth size.

“Teeth can tell us a lot about human evolution because well-preserved ancient teeth are particularly important to archaeologists, shedding light on the stages when we transitioned to cooked food and when human teeth began to shrink in size. But little is known about the genetic basis of variation in tooth size and shape in modern human populations, partly due to difficulties in measuring teeth,” said Adhikari at UCL. statement. “We have now identified numerous genes that influence the development of our teeth, some of which are responsible for differences between ethnic groups.”

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

However, “our findings do not clarify whether the genes that determine tooth shape have been selected for in evolution because of specific benefits for dental health, so the genes may have been selected for their effects in other areas. Differences in tooth shape that result as a side effect,” explained Andres Ruiz-Linares from UCL and Aix-Marseille University. Researchers simply aren’t sure why genes evolved to affect tooth shape in this way.

“Some genes that contribute to normal variation in tooth size among healthy individuals may also contribute to pathogenic variation, such as undergrowth or other dental health conditions,” said Qing Li of Fudan University. to learn. 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 tooth size may also determine health problems.

Ultimately, “We hope that our findings may be medically useful if people with specific dental problems can undergo genetic testing to aid in diagnosis, or if some dental abnormalities can one day be treated with gene therapy,” Li said.

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