“It’s not unusual for a gene to have multiple functions, but before this we didn’t know what regulated the production of tooth enamel,” said Chrissa Kioussi, an assistant professor in the College of Pharmacy at Oregon State University. “This is the first transcription factor ever found to control the formation and maturation of ameloblasts, which are the cells that secrete enamel.”
In their research, the scientists used mice with their Ctip2 genes deleted. When such mice are born, their undeveloped skin and nervous systems cause them to quickly die. But, by observing which anatomical features are lacking, researchers can draw conclusions about Ctip2’s functions. The scientists noted that the teeth of the newborn mice had no proper enamel coating, and never would have become functional.
“Enamel is one of the hardest coatings found in nature, it evolved to give carnivores the tough and long-lasting teeth they needed to survive,” Kioussi said.
Now that Ctip2’s enamel-building function is known, she said, doctors may one day use tooth stem cells to lay down new enamel. Some laboratory animal experiments have already succeeded in growing the inner parts of teeth, but without enamel, because the genetics of enamel were unknown.
“A lot of work would still be needed to bring this to human applications, but it should work,” Kioussi said. “It could be really cool – a whole new approach to dental health.”
This could especially help many people with chronic tooth enamel problems, including smokers, heavy drinkers and drug abusers (notably methamphetamine users). Not to mention the large percentage of people who simply get the occasional cavity – which starts as a hole in tooth enamel that lets decay spread.