Fragile X syndrome (FXS)


Fragile X syndrome (FXS), also called Martin-Bell syndrome, is the most common type of inherited intellectual disability (formerly called mental retardation). Symptoms of FXS are life long, but they range from mild to severe. Symptoms are typically more severe in males than females.
Individuals with FXS inherit a mutated gene from their parents. This mutated gene is unable to produce enough of a protein (called the familial mental retardation protein) that is needed for the body's cells, especially the brain cells, to develop and function normally. The amount of protein that can be produced varies among patients, and partially determines the severity of the disorder.
Patients may also experience other symptoms, including social anxiety, attention deficits, speech and language disorders, seizure disorders, and increased sensitivity to sensory stimuli. A patient's life expectancy is largely dependent on the severity of his/her intellectual disability.
About one out of 4,000 males and one out of 8,000 females are born with FXS each year in the United States.
Although there is currently no cure for FXS, treatments and therapies have been shown to help FXS patients live healthy and relatively normal lives. No matter how serious a patient's learning disability, he/she is capable of learning new things. Most children with FXS are able to develop basic academic skills, although they may need more time to learn or may require special teaching methods. Many adults are able to live independently and maintain jobs. Early intervention and proper care has been shown to increase a patient's long-term prognosis.

Related Terms

Attention deficit, autism, behavioral therapy, cognitive disabilities, DNA test, familial mental retardation protein, FMRP, FMRP1, genetic disorder, genetic mutation, inherited disorder, intellectual disabilities, intellectual quotient, IQ, learning disabilities, macro-orchidism, Martin-Bell syndrome, mental retardation, mutated gene, occupational therapy, physical therapy, social anxiety, speech and language disorders, X-chromosome, X-linked, X-linked dominant.