Fragile X Syndrome
How common is it?
What causes it?

Fragile X Syndrome
Fragile X Syndrome refers to a condition in both boys and girls in which they experience some degree of mental retardation or learning problems, hyperactivity, anxiety and mood problems, seizures, problems with learning visual and spatial skills, and, in some children, autistic symptoms. 

How common is it?
About 1 in 4000 males and 1 in 6000 females of all races and ethnic groups have the FMR1 gene that causes Fragile X Syndrome.  Usually boys are more seriously affected than girls. About a fifth of the boys have autism.

What causes it?
Fragile X Syndrome is caused by the FMR1 gene on the X chromosome, which cannot manufacture the protein it usually makes.

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