Scientists pinpoint gene responsible for tooth root formation in mammals

Investigators from the State University of New York at Buffalo have isolated the gene responsible for initiating normal tooth root formation in mammals and determined that tooth crown and root growth appear to be governed by separate genetic processes. Scientists from the UB School of Medicine and Biomedical Sciences tracked the development of a laboratory animal missing the gene responsible for encoding a protein in the nuclear factor I family.

From the American Dental Association:
Scientists pinpoint gene responsible for tooth root formation in mammals

Investigators from the State University of New York at Buffalo have isolated the gene responsible for initiating normal tooth root formation in mammals and determined that tooth crown and root growth appear to be governed by separate genetic processes.

Scientists from the UB School of Medicine and Biomedical Sciences tracked the development of a laboratory animal missing the gene responsible for encoding a protein in the nuclear factor I family, according to a UB news release.

This family of proteins is associated with the replication of adenoviruses but the genes responsible for the development of the proteins exist only in multicellular organisms, suggesting a role in the development of complex life forms, explained Richard Gronostajski, Ph.D., a UB professor of biochemistry.
In the laboratory animal missing the gene to encode the nuclear factor I-C protein, development appeared to proceed normally until the mouse was weaned to standard food, at which point it became stunted and died. Further investigation showed that while the mouse had normal tooth crowns, they lacked roots embedding the teeth into the jaw.

“The tooth is a little mini-organ that develops through a mechanism of its own,” Dr. Gronostajski explained. “The signals that are important for root growth turn out to be different from the signals that initiate crown growth. We don’t know if the defect affects the tooth itself and the signals between those two tissue layers, or if the signal originates in the surrounding tissue.”

“This is the first mutation in mice that predominately affects the roots of teeth and how they grow out of the crown,” he added. “If we can understand how this gene functions, we will know a great deal about root disease, root loss and the causes of tooth loss.”

SOURCE: State University of New York at Buffalo news release, 3/25/03.