Fragile X chromosome

This code identifies Fragile X syndrome, a genetic disorder caused by a mutation in the FMR1 gene on the X chromosome. It is the most common inherited cause of intellectual disability and is associated with a range of developmental, behavioral, and physical characteristics.

Assign this code when documentation confirms a diagnosis of Fragile X syndrome, typically based on genetic testing results. This code is appropriate for patients presenting with intellectual disability, developmental delays, autism spectrum disorder, or characteristic physical features where Fragile X has been confirmed as the underlying etiology.

• Always ensure genetic testing results or a definitive clinical diagnosis of Fragile X syndrome are present in the medical record.
• Code any associated intellectual disabilities (e.g., F70-F79) or autism spectrum disorders (F84.0, F84.3, F84.5) as secondary diagnoses.
• Do not confuse with other chromosomal abnormalities unless Fragile X is specifically documented.