History of Fragile X Syndrome

1910 Thomas Hunt Morgan demonstrates that when a gene is located on the X chromosome of the fruit fly, the characteristic appears more frequently in males than in females.

???? Hemophilia exhibits a similar pattern of X-linked inheritance.

1943 Martin and Bell show that a particular form of mental retardation is X-linked.

1969 Herbert Lubs finds visual proof of the linkage of mental retardation and the X chromosome