Fragile X Syndrome

Fragile X syndrome (FXS) is recognized as the most common identifiable genetic cause of intellectual disability (ID) and autism spectrum disorder (ASD). Fragile X syndrome is caused by the absence or reduction of expression of the fragile X messenger ribonucleoprotein (FMRP) and is associated with a variety of behavioral, physical, and medical problems. Medical problems commonly seen in the disorder need to be managed to prevent impacts on learning, development, and behavior. Specific patterns of cognitive, language, and adaptive strengths and weaknesses are typically present and can be utilized to tailor supportive educational, therapeutic, and behavioral programming to the needs of the individual with FXS. Behavioral issues and comorbid psychiatric diagnoses including attention-deficit/hyperactivity disorder (ADHD), anxiety disorders, irritability, and aggression are often also managed through supportive treatment with psychopharmacology to ameliorate limiting symptoms. This includes the frequent use of stimulants, alpha-agonists, selective serotonin reuptake inhibitors (SSRIs), antipsychotics, and in some cases, mood stabilizers. Recent major advances in the understanding of the underlying neurobiology of FXS will hopefully lead to new treatments targeted to neural mechanisms that will improve upon currently available treatments.