The genes also allow sharks to replace rows of their teeth using a conveyer belt-like system.
A research team, led by Dr. Gareth Fraser from the University of Sheffield in the United Kingdom, has identified how a special set of epithelial cells form, called the dental lamina, which are responsible for a shark’s ‘lifelong dental regeneration.’
Interestingly, humans also possess the same genes that drive formation of dental lamina; the cells are responsible for the growth of baby and adult teeth. Once a person's adult teeth are fully formed, however, dental lamina is lost.
Dr. Fraser and colleagues say that these tooth-making genes found in sharks are conserved through 450 million years of evolution, and probably made the first vertebrate teeth.
These ‘tooth’ genes, therefore make all vertebrate teeth from sharks to mammals; however in mammals like humans, the tooth regeneration ability, that utilizes these genes, has been highly reduced over time.
Commenting on the finding, Dr. Fraser says: "We know that sharks are fearsome predators and one of the main reasons they are so successful at hunting prey is because of their rows of backward pointing, razor-sharp teeth that regenerate rapidly throughout their lifetime, and so are replaced before decay.”
“The Jaws films taught us that it is not always safe to go into the water, but this study shows that perhaps we need to in order to develop therapies that might help humans with tooth loss,” he added.