Fragile X Test (FXS)

The Fragile X Syndrome test is a molecular genetic test that analyses the FMR1 gene on the X chromosome to determine the number of CGG trinucleotide repeats. An abnormal expansion of these repeats leads to silencing of the FMR1 gene, which prevents the production of the FMRP protein, essential for normal brain development.
This test is used to diagnose:
Fragile X Syndrome (FXS) in individuals showing developmental delays, learning disabilities, or autism-like behavior.
Carrier status in individuals with a family history of FXS.
Related conditions like Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI) in premutation carriers.
Testing is performed using:
PCR to estimate CGG repeat size.
Early diagnosis allows for timely interventions, appropriate therapies, and genetic counselling for affected individuals and their families.