Fragile X Syndrome: A genetic disorder marked by a large number of “weak arm” (mutations) on the X chromosome. There is a suspected concurrence between Fragile X syndrome and Autism. Studies suggest that 1/3 of those with Fragile X syndrome will have an Autism diagnosis. Fragile X syndrome occurs in about 1 in 4,000 males and 1 in 8,000 females. Please Learn More about Fragile X syndrome by using the button below.