Genome sequencing has taken a huge step forward over the last decade. The first bacterial genome was only sequenced in 1995 - almost two decades later, we've sequenced thousands of bacterial and hundreds of eukaryotic genomes. Every year the process becomes faster and cheaper. So it's a surprise that the Internet's favorite furry friend has been neglected. Now, however, this grave injustice has been rectified, and the outcome may help answer some important evolutionary and medical questions.
Felis catus has not been neglected entirely. Shotgun sequencing, a cheaper method that inevitably leaves gaps, was done in 2007, but it is only now that a full sequencing with annotation of the moggy's genome has been completed. The work was an international collaboration led by St Petersburg State University.
The announcement has been made in Gigascience where the authors note, “Domestic cats enjoy an extensive veterinary medical surveillance which has described nearly 250 genetic diseases analogous to human disorders.” Other mammals may also share many of these, or other conditions, with humans, but we are less likely to know about those who don't share our homes.
The feline genome is of interest for another reason. It is, as the authors point out, “A highly conserved ancestral mammal genome organization.” While other species have changed greatly with time, cats appear to have stuck with what works. This is particularly interesting because their relationship with us has changed dogs' genetic make-up greatly, but cats hardly at all, a difference that cannot be explained purely by the shorter period they have been domesticated.
Of course, every cat is different. When the human genome was sequenced samples were collected from many people to protect the anonymity of those whose DNA was used. Cats have not been thought in need of the same protection. The authors report using the whole genome of a female Abyssinian named Cinnamon who lives at the University of Missouri, while additional analysis was done on Boris from St. Petersburg, Russia. Sylvester, a European wildcat (Felis slivestris silvestris) thought to be similar to the species before domestication, was “lightly” sequenced to provide insight into how cats have changed since domestication.
From this process 21,865 protein-coding genes were identified and annotated, based on comparisons with other species. This represents 56% of the feline genome. The results are available in a browser named the Genome Annotation Resource Fields or GARfield.
