Gene in Dogs May Explain Human Dwarfism

I know this sounds off-topic for a human-health blog, but bear with me in this: Dog researchers have discovered a gene event that may have implications for understanding human dwarfism.

Published early in Science, scientists found that those cute-looking short-legged dog pedigrees that include Bassett Hounds and Dachshunds are products of a single mutational event in the dog evolution.

Somewhere in evolution when dogs separated from the wolves, a mutation caused certain dogs to have short legs, and that mutation was preserved through time to create the modern-day short-leg breeds like the dachshund, corgi, Pekingese and basset hound. In these dogs, scientists found an extra copy of a gene that codes for a growth-promoting protein called fibroblast growth factor 4 (FGF4). The extra gene copy results in over-production of the FGF4 protein which the scientists hypothesize turn on growth receptors at the wrong time during fetal development. In short-leg breeds, the growth plates of the legs get calcified during development, resulting in short legs with curved appearance like the one pictured. This kind of dwarfism is known as chondrodysplasia and found in dachshund, corgi, Pekingese and basset hound, but not in the miniature toy dog breeds.

Humans too, have a similar growth disorder called hypochondroplasia, a form of dwarfism, so scientists are trying to find out if there’s a FGF4 connection in humans too.

via: Science Direct

Image: Flickr