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Fragile X

The Fragile X blood test is used to diagnose Fragile X syndrome, a genetic disorder that is the most common known cause of inherited intellectual disability and autism. The Fragile X test measures the number of repeats of a specific DNA sequence located on the X chromosome, which is called the Fragile X Mental Retardation 1 (FMR1) gene. Fragile X syndrome is caused by a genetic change in the FMR1 gene, which leads to the production of an abnormal form of a protein called FMRP. The severity of Fragile X syndrome is related to the size of the abnormal repeat expansion in the FMR1 gene. People with smaller expansions may have only mild intellectual disability, while those with larger expansions may have more severe intellectual disability and other symptoms such as autism, attention deficit hyperactivity disorder (ADHD), and behavioral and emotional problems. The Fragile X blood test is a simple and reliable way to diagnose Fragile X syndrome. The test is usually performed using a small blood sample, which is then analyzed in a laboratory to determine the size of the repeat expansion in the FMR1 gene. A positive result on the Fragile X test indicates that an individual has Fragile X syndrome, while a negative result means that the person does not have the condition. The test is often used in combination with other tests and evaluations to diagnose Fragile X syndrome and to determine the most appropriate course of treatment.

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