Fragile X syndrome is a genetic disorder that causes a wide range of developmental problems, including learning disabilities, cognitive impairment, and behavioral challenges. It is the most common inherited cause of intellectual disability and is caused by mutations in the FMR1 gene on the X chromosome. People with Fragile X syndrome may also have physical characteristics such as a long face, large ears, and a prominent jaw. Treatment typically involves therapy and medications to manage symptoms. Researchers are studying the underlying causes of Fragile X syndrome and developing new treatments to improve outcomes for individuals with the disorder.