Variation of BMP3 Contributes to Dog Breed Skull Diversity

Cancer Genetics Branch, National Human Genome Research Institute, Bethesda, Maryland, United States of America.
PLoS Genetics (Impact Factor: 7.53). 08/2012; 8(8):e1002849. DOI: 10.1371/journal.pgen.1002849
Source: PubMed


Author Summary
As a result of selective breeding practices, modern dogs display a multitude of head shapes. Breeds such as the Pug and Bulldog popularize one of these morphologies, termed “brachycephaly.” A short, upward-pointing snout, a massive and rounded head, and an underbite typify brachycephalic breeds. Here, we have coupled the phenotypes collected from museum skulls with the genotypes collected from dogs and identified five regions of the dog genome that are associated with canine brachycephaly. Fine mapping at one of these regions revealed a causal mutation in the gene BMP3. Bmp3's role in regulating cranial development is evolutionarily ancient, as zebrafish require its function to generate a normal craniofacial morphology. Our data begin to expose the genetic mechanisms unknowingly employed by breeders to create and diversify the cranial shape of dogs.

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