Abstract
Tooth morphology is the result of tissue interactions, many of which involve families of regulatory genes that pattern development. Determining and quantifying the effect of regulatory genes has implications for understanding the mechanisms driving the degree of diversity observed in mammalian dentition. Bone morphogenetic protein 7 (BMP7) is one regulatory gene that is active in the developing tooth. I characterized the morphology and assessed the function of the dentition in BMP7 conditional knockout mice. Mutant molars had short, broad cusps, and extra cusps on the M1 and m1. Wear facets in the mutant mice were different in shape and in the direction that they faced on the tooth. This shows that changes in the expression of BMP7 lead to changes in the morphology and function of the dentition, suggesting that BMP7 could have acted in structuring the amount of dental diversity that is apparent in extinct and extant mammals.
