Too Much Can be a Bad Thing

How Common is Polydactyly and Who has it?

One in every 500 to 1,000 individuals is born with polydactyly. One out of every 1,339 Caucasian babies are born with it, while one in every 143 African American babies has the disorder.

Public figures of celebrities who had this disease include Halle Berry, with an extra left toe on her left foot, Oprah Winfrey, who had the extra toe on her left foot removed, and Henry II the Pious, the High Duke of Poland from 1238 to 1241.

What is Polydactyly and What Causes it?

Polydactyly is the genetic disorder of having an extra finger or toe next to the thumb, big toe, pinky, pinky toe, or centrally in the hand or foot.

The extra digit can be made up of only skin and soft tissue, skin and soft tissue and a bone, or skin, soft tissue, bone, and a joint. The extra digits vary from easy to remove to most difficult to remove in the order listed.

Polydactyly affects the gene GLI3 and the proteins involved with GLI3. People with normally functioning GLI3 proteins have normal fingers and toes developed during embryonic development. When the GLI3 proteins are affected, they cause a finger or toe to split in half, which can be seen when the baby is born, or through ultrasound.

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Type of Mutation and Type of Inheritance

The way that the GLI3 section of proteins previously mentioned works is that it deletes or changes sections of DNA in the 7 chromosome.

Also, although it may seem surprising because it is so rare to see, Polydactyly is a dominant trait. Most people who have the disorder have the extra digit removed in the first or second year of their lives, so it is rare to see it in everyday life. Another reason why it is rare to get it even though it is dominant is due to the fact that the Polydactyly gene is recessive to other genetic disorders.

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Treatment and Identification

The treatment for Polydactyly is very simple, as it is just a surgical removal of the extra finger or toe in year one of two of the patient's life. As previously mentioned it can be identified in the womb through ultrasound, or seen when the baby is born. There is no reason to treat the disorder before birth, as the procedure to fix it is so simple.

Another way to treat it when there is no bone or joint is to put a clip on the base of the extra digit, cutting off blood flow and allowing the dead part to fall off. After doing either procedure, visits to the doctor will need to be made to check up on healing, as a surgeon will have to cut around ligaments and bones to remove the body part.

There are virtually no ethical problems with treatment, and the only cultural problems will be with cutting into the body and the use of anesthesia for removal.


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