KEY POINTS:
The first full genetic map of a cat - a domestic pedigree Abyssinian - is shedding light on a common cause of blindness in humans and may offer insights into Aids and other diseases.
And the cat genome, say researchers, shows some surprising qualities that cats and humans
appear to have uniquely in common.
"We can start to interpret them in terms of one of evolution's special creations, which is also probably one of the greatest predators that ever lived," said Dr Stephen O'Brien of the US National Cancer Institute. He helped lead the study reported in the journal Genome Research.
The cat, named Cinnamon, is descended from lab cats bred to develop retinitis pigmentosa, a degenerative eye disease that causes blindness and that affects one in 3500 Americans.
Dr O'Brien said a study of her genes could help uncover some of the causes of the incurable condition and might help find treatments for it.
Cats also were important for studying other diseases.
"The reasons why the cat genome is cool go on for about an hour."
People get HIV, which causes Aids, while the feline immunodeficiency virus causes a similar disease in cats. The discovery of feline leukemia virus in the 1960s led scientists to realise that viruses can cause cancer.
"This led to oncogene development and some of the best smart drugs that we have for cancer," Dr O'Brien said.
Like other mammals, the cat has around 20,000 genes. Genome researchers have learned that much of the genetic code is made up of "non-coding regions" of DNA, areas that do not make up genes but are important for biology.
Researchers can compare the cat genome to those of the six other mammal genomes - the human, chimpanzee, mouse, rat, dog, and cow - to figure out differences in biology, evolution and disease.
Dr O'Brien said this comparison already showed something interesting that happened as so many different species evolved from a tiny, shrew-like ancestor that outlived the dinosaurs.
"The order of genes in the cat is remarkably similar to the order of genes in the ancestor of all placental mammals," he said.
"The two species that have that similarity are humans and cats. Other species have a reshuffled genome, like a deck of cards.
"The cat and the humans are pretty much similar to the way it was, which means the good model didn't get fiddled with."
Pedigree cats and dogs are highly inbred, and Cinnamon especially so.
Dr O'Brien said: "For the first time, we have seen in ... detail all these genes that this cat has as well as the footprints of inbreeding and cat domestication.
"One thing I'd like to discover is the genes for good behaviour in the cats - the genes for domestication, the things that make them not want to kill our children but play with them."
