Hulk Dog

Yow. From the Victoria, Canada, Times-Colonist:

People mistake her for a pitbull with a pinhead, but Wendy the whippet is one rare breed.

So rare that the Central Saanich dog recently graced the New York Times. She also had several of her photos shown on The Today Show, all because of a rare genetic mutation that has led to her being the Incredible Hulk of dogs...

...Wendy was recently part of a genetics study done in the U.S. on mutation in the myostatin gene in whippets, which resemble greyhounds in appearance. The National Institute of Health study reported that whippets with one single defective copy of the gene have increased muscle mass that can enhance racing performance in the breed, known for speeds up to 60 kilometres an hour.

But whippets with two mutated copies of the gene become "double-muscled," like Wendy. It has been seen before in one human, and also in mice, cattle and sheep, says the study.