NEUROBEHAVIORAL

Fragile X Syndrome

Fragile X syndrome (FXS), originally known as Martin-Bell syndrome, is a rare genetic condition that causes intellectual disability, anxiety, social avoidance, behavioral and learning challenges, and various physical characteristics. It is the leading known genetic cause of both inherited intellectual disability and autism spectrum disorder.

FXS patients are born with a mutation in a gene called FMR1, which leads to dysregulation of the endocannabinoid (EC) system and may result in the core cognitive, social, and behavioral symptoms seen in FXS. The impairment can range from learning disabilities to severe cognitive or intellectual disabilities. Patients with FXS exhibit autism-like symptoms including social anxiety and avoidance, cognitive impairment, intellectual disability, mood swings, attention deficiency, irritability, and increased risk for aggression.

An estimated 80,000 patients in the US are believed to have FXS, based on FXS prevalence estimates of approximately 1 in 4,000 to 7,000 in males and of approximately 1 in 8,000 to 11,000 in females.

22q11.2 Deletion Syndrome

22q11.2 deletion syndrome (22q) is a disorder caused by a small missing piece of the 22nd chromosome. The deletion occurs near the middle of the chromosome at a location designated q11.2. It is considered a midline condition, with physical symptoms including characteristic palate abnormalities, heart defects, immune dysfunction, and esophageal/GI issues, as well as debilitating neuropsychiatric and behavioral symptoms, including anxiety, irritability, social withdrawal, ADHD, cognitive impairment, and autism spectrum disorder.

It is estimated that 22q occurs in 1 in 4,000 live births, suggesting that there are approximately 80,000 people living with 22q in the US, and there are currently no FDA-approved treatments for this disorder.