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What is Fragile X Syndrome?
Fragile X syndrome (FXS) is the most common inherited cause of autism and intellectual disabilities. It affects 1 in 4,000 boys and 1 in 6,000 girls worldwide.Fragile X syndrome occurs when a single gene on the X chromosome shuts down. This gene makes a protein needed for normal brain development. In FXS it does not work properly, the protein is not made, and the brain does not develop as it should.
Fragile X syndrome is a genetic disorder characterized by mild-to-moderate intellectual disability. The average IQ in males is under 55, while about two thirds of females are intellectually disabled. Physical features may include a Long and narrow face; High-arched palate; Large, protruding ears (both); Hyperextensible finger joints;Hyperextensible (‘double-jointed’) thumbs; Flat feet; Soft skin; Postpubescent macroorchidism (large testicles in men after puberty); and Hypotonia (low muscle tone).
Synonyms of Fragile X Syndrome
- fragile site, folic acid type, rare, Fra(X)(Q27.3)
- marker X syndrome
- Martin-Bell syndrome
- Fragile X Syndrome from the National Organization for Rare Disorders (NORD). New
- Fragile X syndrome from the Genetics Home Reference of the U.S. National Library of Medicine of the National Institutes of Health (NIH) New
- Fragile X Syndrome (FXS) the Centers for Disease Control and Prevention (CDC) is working to learn more about fragile X syndrome and fragile X-associated disorders to improve the health and well-being of people with these conditions.
- Fragile X Research Foundation
- Fragile X Society [UK] New
- National Center on Birth Defects and Developmental Disabilities (NCBDDD)
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) of the National Institutes of Health (NIH).
- Intellectual and Developmental Disabilities Branch (IDDB) of the NIH / Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD).
- Genetics Home Reference: Your Guide to Understanding Genetic Conditions from the U.S. National Library of Medicine of the National Institutes of Health (NIH)
- The Arc offers support to families affected by cognitive, intellectual and developmental disabilities and fosters research and educational programs on the prevention of mental retardation. The Arc secures opportunities for choice in education, housing, employment, and entertainment.