Spontaneous emergence of overgrown molar teeth in a colony of Prairie voles (Microtus ochrogaster)

Abstract

Overgrown molars in some prairie voles could help explain the development of continuously growing teeth in rodents, say US researchers. All rodents have incisors that grow continuously throughout their lives but voles also possess continuously growing molars. Andrew Jheon at the University of California, San Francisco, and co-workers noticed that three animals in their vole colony showed unusually large molar protuberances and that these characteristics were passed on to their offspring. In some cases, the extra-large molars became infected or even broke through into the brain. The incisors of the affected voles appeared to be normal, leading the researchers to suggest that there are important genetic regulatory differences between incisors and molars. Specifically, the unrestricted molar growth may be caused by mis-regulation of a unique group of molar dental stem cells.

Keywords

continuously growing teeth / molar phenotype / mutation / stem cell regulation / voles

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