Fragile X syndrome
Fragile X syndrome (FXS) is a genetic condition, marked by inherited intellectual disability, especially in boys. About half of all children diagnosed with fragile X syndrome also meet criteria for autism spectrum disorder. In addition to intellectual disability, there are distinguishing physical features as well, including elongated face, protruding ears and low muscle tone.
Anyone diagnosed with fragile X syndrome will present on the continuum of learning disabilities, from displaying normal intelligence to severe intellectual disability. On average, boys with a complete fragile X mental retardation 1 (FMR1) will have an IQ around 40. Additionally, between 15 and 60% of cases are co-current with autism spectrum disorder, and it is suspected that fragile X syndrome is the genetic cause of autism in such cases.
Fragile X syndrome results from a mutation in the FMR1 gene, which is on the X chromosome. There are currently no treatments or cures for fragile X syndrome. The best that medical science can offer are medications for various symptoms, attempting to minimize the secondary characteristics of the disease, such as anxiety, ADHD, hypersensitivity, and problems with working memory. Additionally, individuals with FXS are at a greater risk of developing seizures, estimated around 14% of all boys and 6% of girls with fragile X syndrome.