What percent of people are affected by Ectrodactyly?

Answer 1

The short answer is 50%; however, there are many factors that influence this number. This percentage is limited to cats, although polydactylism does occur in most species, including canines. There are currently not enough completed studies to list percentages of polydactylism in other species. Polydactylism is considered, by most, to not be a problem.

In the world of genetics, the polydactyl gene (Pd gene) is an autosomal dominant gene. This means that you cannot have a polydactyl offspring without having at least one polydactyl parent, and there are no known recessive genes that would allow the trait to pop-up generations down the road. They either have the poly Pd gene and express it, or they do not and it cannot be passed on to future generations.

Although many breeds of cats can be polydactyl, one specific registered breed, the Maine Coon, seems to be most notable of the breeds that express polydactylism. This is due to the fact that the original stock (or Foundation cats) was selected from the area of Eastern United States and Canada and in particular, the State of Maine. This wild, or feral, population was estimated to be 40% polydactyl, although this number is not documented well enough to be considered completely accurate.

That percentage of polydactyl Maine coon cats does indicate that if left in the wild with random breeding, the number will approach the 50% mark in the absence of any outside influences (mainly man).

Once that specific breed was established, it was frowned upon by Cat Associations and "elitist breeders." Pressure was put onto Maine Coon breeders to cull the polydactyls because of this genetic deformity of their toes. The Maine Coon polydactyl was facing near extinction a few years back, with an estimated population of 1 to 2% of the registered Maine Coon breed. Today there is a movement to re-establish the Maine Coon polydactyl back into breeding program and into the shows of the various Cat Associations. Although this trend is being seen more in Europe, there is resurgence in the Western Hemisphere as well.

So, referring to the cat population in general, polydactylism is still somewhat rare; however, most individual litters involving a polydactylism has about 50% or more of the offspring being polydactyl. Again, one parent must be a polydactyl themselves or the gene cannot be passed along. If one parent is a polydactyl and one is not, the chance of the litter being polydactyl is 50%.

Quite often the overall percentage will be higher due to the fact that a homozygous parent can be involved (two copies of the Pd gene). This will in theory give you a 100% poly litter. In other cases, where both parents are polydactyls (but not homozygous), it is said that, statistically, they will have a 75% poly litter.

This is a harmless genetic trait and is in no way the result of congenital defects, environmental factors, or the result of other genes or breeding combinations.

A non-commercial website with more information about feline polydactylism:

http://www.polytrak.net

tracks these numbers and trends into a database for observation. Presently it is showing 420 kittens listed of which 58% are polydactyl. This number reflects the average of the three above listed breeding combinations. You can find much more information about polydactyl Maine Coons on the above site, or you can search the internet for Maine Coon polydactyls and find many websites that discuss this topic.

Answer 2

1 out of every 500 people depending on the ethnic group 1 out of every 500 people depending on the ethnic group

Answer 3

According to Nip/Tuck the chances are one in a million babies are born with it