The development of baby teeth depends on several newly identified genes.

By analyzing the genetic code of 6,000 people in Finland and the United Kingdom, researchers found gene variants linked with the time the first tooth appears and with the number of teeth by age one.

The findings appear in Friday's issue of the journal PloS Genetics.

"Our findings should provide a strong foundation for the study of the genetic architecture of tooth development, which as well as its relevance to medicine and dentistry, may have implications in evolutionary biology since teeth represent important markers of evolution," Marjo-Riitta Jarvelin of the School of Public Health at Imperial College London and her colleagues concluded.

One of the identified genes was associated with a 1.35 times higher risk of requiring costly orthodontic treatment by age 30, the researchers found.

Previous studies have linked some of the genes with the development of the skull, jaws, ears, fingers, toes and heart.

"We hope also that these discoveries will increase knowledge about why fetal growth seems to be such an important factor in the development of many chronic diseases," Jarvelin said in a release.

The discovery may lead to innovations in the early treatment and prevention of congenital dental problems, the researchers said.