Fragile X Syndrome History And Genetics

Fragile X Syndrome was discovered in 1943 by a man named James Purdon Martin (pictured) and a woman named Julia Bell. This is the reason  the disorder is often called Martin-Bell syndrome as well. The disorder was discovered when Martin and Bell investigated and collected data from a family with multiple men in their line who where mentally handicapped. For a more in-depth history of the disorders discovery, look here.

On to genetics, this disorder can be passed from a mother to her son or daughter, but a father can only pass the trait to his daughter. This disorder is caused by a mutation on the X chromosome. And since males have an X and a Y chromosome, a male can only either have the disorder or not have it. However, since females have two X chromosomes, a female can either have the disorder, not have it, or be a carrier of the disease but not have it be expressed.