Why Do Some Cats Have Thumbs?

Theres nothing cuter than a kittys paws, right? When it comes to polydactyl catsor cats born with more than the usual number of toes on their pawsthe extra toes just compound the cuteness. While most cats have five toes on their front paws and four toes on their back paws, polydactyl cats can have six (or more!) on each paw.

Vanessa Cavanagh Polydactyly is caused by a genetic mutation in a dominant gene and usually results in the formation of anywhere between four to seven toes on a kittys paws. Its important to note that feline radial hypoplasia, a condition that is often confused with polydactyly, can be extremely detrimental to a cats health.

If cats with feline radial hypoplasia are bred, it can cause severe paw deformities in subsequent generations. Because polydactyl cats have wider, larger paws, theyre better able to balance on various surfaces, climb, hunt, and capture their prey. With the help of their large, wide paws, polydactyl cats made excellent mousers and could keep the ships supplies vermin-free.

Polydactyl cats are most commonly found in Western England, Wales, Canada, and the Eastern United States, and their prevalence in those regions is often credited to their days on trans-continental ships. After he was gifted a white, polydactyl cat named Snow Ball by a ships captain, Ernest Hemingway developed a serious affection for these multi-toed kitties.

Are cats with thumbs rare?

Polydactyly Is Caused by a Genetic Mutation. The front paws are most often affected by polydactyly, but it can also occur on the hind paws; it’s extremely rare for a cat to have polydactyly on all four paws.

Why does a cat have thumbs?

In some cats, the extra thumbs on the front feet are opposable, making it easier for the cat to manipulate small objects. Long ago, sailors called their polydactyl felines “ship’s cats” and considered them good luck because they were excellent mousers and could even climb the rigging in pursuit of their prey.

Are polydactyl cats healthy?

Polydactyl cats are generally healthy and have an average life span. But those extra toes can grow at unusual angles and cause problems with the cat’s claws and skin on the foot.

Are polydactyl cats inbred?

Genetically, polydactylism is a simple autosomal (not related to gender) dominant trait. Cats with extra toes have the dominant gene, Pd. … Inbreeding would increase the percentage of polydactyl offspring, but there will always be a few normal-toed kittens in the litter, because of that recessive gene.

A polydactyl cat is a cat with a congenital physical anomaly called polydactyly (or polydactylism, also known as hyperdactyly), which causes the cat to be born with more than the usual number of toes on one or more of its paws. Cats with this genetically inherited trait are most commonly found along the East Coast of North America (in the United States and Canada) and in South West England and Wales.[citation needed]

[1] The SHH protein is an important signalling molecule involved in patterning of many body elements, including limbs and digits. The condition seems to be most commonly found in cats along the East Coast of North America (in the United States and Canada ) and in South West England , Wales and Kingston-upon-Hull .

Although there is some controversy over whether the most common variant of the trait originated as a mutation in New England or was brought there from Britain , there seems to be agreement that it spread widely as a result of cats carried on ships originating in Boston, Massachusetts , and the prevalence of polydactyly among the cat population of various ports correlates with the dates when they first established trade with Boston. Genetic work studying the DNA basis of the condition indicates that many different mutations in the same ZRS area can all lead to polydactyly. In the case of preaxial polydactyly of the Maine Coon cat (Hemingway mutant) a mutation of the cis-regulatory element ZRS (ZPA regulator sequence) is associated.

Normally SHH is expressed in an organiser region, called the zone of polarizing activity (ZPA) on the posterior limb side. [12][13] An identical sequence at this position serves the same function in human and mice and cause similar symptoms when mutated. In the concrete preaxial form of the Hemingway ( Hw ) mutant the variation is induced by a single point mutation in a noncoding cis-regulatory element for SHH.

In an extensive phenotypic variation like this, one or more complete digits at each single limb are developed including nerves, blood vessels, muscles and ligaments. The summarized small random changes on all layers build the raw material and the process steps for the generation of the plastic variation. “Point mutations in a distant sonic hedgehog cis-regulator generate a variable regulatory output responsible for preaxial polydactyly” .

“Biased Polyphenism in Polydactylous Cats Carrying a Single Point Mutation: The Hemingway Model for Digit Novelty”. “Is it true many New England cats have extra paws because Boston ships’ captains considered them lucky?” “Opposing functions of the ETS factor family define Shh spatial expression in limb buds and underlie polydactyly” .

Q: I’ve had cats before, but none ever looked like the cat I adopted this week from the shelter. Both of her front paws have the normal four toes plus three thumbs instead of one. I’ve never seen a cat with so many thumbs. What is this called? Should the extra thumbs be surgically removed?

Long ago, sailors called their polydactyl felines “ship’s cats” and considered them good luck because they were excellent mousers and could even climb the rigging in pursuit of their prey. I want him with me as long as he is happy and comfortable, but I don’t want him to suffer, so I’ll have his veterinarian euthanize him when his quality of life is poor.

Fortunately, Dr. Alice Villalobos, a veterinary oncologist who focuses on palliative and hospice care, developed a detailed quality of life scale that I have found valuable with my own pets, and I’m sure it will help you, too. Hurt: Adequate pain control and effortless breathing are at the top of this quality of life scale. I hope the remaining time you and Marty have together is full of tender joy and gentle kisses.

History and folklore[edit]

Polydactyly is a congenital abnormality that can be inherited in an autosomal dominant manner. Some cases of polydactyly are caused by mutations in the ZRS, a genetic enhancer that regulates expression of the sonic hedgehog (SHH) gene in the limb.Normal cats have a total of 18 toes, with five toes on each fore paw, and four toes on each hind paw; polydactyl cats may have as many as nine digits on their front or hind paws. Both Jake, a Canadian polydactyl cat, and Paws, an American polydactyl cat, were recognised by Guinness World Records as having the highest number of toes on a cat, 28.

Breeding[edit]

American Polydactyl cats are bred as a specific cat breed, with specific physical and behavioral characteristics in addition to extra digits.The American Polydactyl is not to be confused with the pedigree Maine Coon Polydactyl. The polydactyl form of the Maine Coon is being reinstated by some breeders.

Genetics[edit]

In the case of preaxial polydactyly of the Maine Coon cat (Hemingway mutant) a mutation of the cis-regulatory element ZRS (ZPA regulator sequence) is associated. ZRS is a noncoding element, 800 kilobasepairs (kb) remote to the target gene SHH. An ectopic expression of SHH is seen on the anterior side of the limb. Normally SHH is expressed in an organiser region, called the zone of polarizing activity (ZPA) on the posterior limb side. From there it diffuses anteriorly, laterally to the growth direction of the limb. In the mutant mirroring smaller ectopic expression in a new organiser region is seen on the posterior side of the limb. This ectopic expression causes cell proliferation delivering the raw material for one or more new digits.Polydactyly is a spontaneous complex phenotypic variation, developed in one generation. In the concrete preaxial form of the Hemingway (