Does your feline have extra toes?

Most cats have 18 toes; five toes on each of their front feet, and four on the back.  My cat, Mandy Pawtinkin, is blessed with 22 toes.  She has a congenital physical anomaly called polydactyly (Greek for ‘many digits’).  It is a genetic mutation that causes cats to be born with more than the usual number of toes on one or more of its paws.

Having practiced as a veterinarian in Ontario for several years before returning to my native Nova Scotia, I was intrigued by what appeared to be many more polydactyl cats in our region.  Doing some research, I found out there is indeed a higher incidence of polydactyl cats in the Northeastern US, Halifax, and a pocket in England and Wales.  Being a Lunenburger, I was especially delighted to find that there is a maritime connection involving these fascinating cats.

It is believed that English Puritans might have taken polydactyl cats on their ships to Boston during the mid-1600s.  The offspring of these cats are believed to have then travelled on trading ships from Boston to Halifax, which could explain why these areas have higher than normal incidence of polydactyly.  Polydactyl cats were thought to be lucky by sailors.  They found their way onto boats, their extra toes giving them added balance on ships in stormy weather.  They were also thought to be better mousers.  It has been said that there are fewer polydactyl cats in Europe because many of these cats were considered witches’ familiars and hence destroyed.

Polydactyl cats are sometimes referred to as “mitten cats,” or “Hemmingway cats”.  The latter name refers to the author Ernest Hemingway, who was given his first polydactyl cat, Snowball, by a ship’s captain and drinking buddy.  Today, due to unrestrained breeding, nearly 50 of Snowball’s descendants still live at the Hemingway home in Key West, Florida.

Genetically, polydactylism is a simple autosomal (unrelated to gender) dominant trait.  Cats with extra toes have the dominant gene PD.  A cat needs only one copy of the gene from either parent to have the trait.  Therefore, if one parent has extra toes, 50% of the kittens will have it too.  Polydactylism doesn’t affect cats adversely.  It is simply an enchanting quirk.  The toenails associated with the extra toes tend to be normal nails, although the extra toe occasionally might be incompletely formed and the nail bed deformed, leading to claw problems like ingrown or overgrown nails.  Like all kitty toenails, the extra ones require regular trimming.

If you are wondering, the most toes ever found on a cat, reported in 1974, was 32 toes, eight on each paw.  The current record holder is Tiger, a 27-toed kitty from Alberta, Canada.

Written by: Dr. Croft