- Last edited on April 30, 2020
This is an old revision of the document!
Fragile X Syndrome (FXS)
Primer
Fragile X Syndrome (FXS) is an X chromosome-linked dominant disorder caused by the amplification of a CGG repeat in the 5′ untranslated region of the fragile X mental retardation gene 1 (FMR1). It is the most common inherited cause of intellectual disability.
Epidemiology
There is a prevalence of 1 in 3600 to 4000.[1]
Comorbidity
Individuals have very high rates of anxiety disorders (over 80%), attention-deficit/hyperactivity disorder (over 50%), autism (30 to 35%), and mood instability and aggression.[2]