Have you ever wondered why dog breeds such as dachshunds and basset hounds have legs that are noticeably short and stubby? Recently, US and British researchers have investigated on this matter and found out that it was due to the mutation of a single gene. This mutation occurred in the early evolution of dogs and the mutated gene is a slightly altered copy of a gene called fibroblast growth factor 4, also known as FGF4. Short-legged dogs have this mutated gene as their second growth-related gene whereas most dogs only have one growth-related gene.So, where does this retrogene of FGF4 came from? The researchers examined the genes and brought up a conclusion that it seems to be a copy of a wolf gene. This can be quite possible as some modern dog breeds diverged from wolves. This means that a physical trait of quite a few dog breeds were caused by one retrogene being inserted at some point within the evolution. Therefore, the researchers are looking forward to see these retrogenes playing larger role in evolution.
posted by: Anna Won-Kyung Jang (42042372)
Original Artical:
http://www.abc.net.au/science/articles/2009/07/17/2629078.htm?
