Fragile X syndrome (FXS) Test

Overview

Fragile X syndrome (FXS) is a hereditary condition. FXS is caused by mutations in a gene known as the FMR1 gene when it was initially found. The FMR1 gene normally produces a protein known as FMRP. FMRP is required for proper brain development. People with FXS do not produce this protein. People with other fragile X-associated disorders have FMR1 gene mutations but normally produce some of the protein.

FXS affects both men and women. Females, on the other hand, frequently experience weaker symptoms than males. The actual number of persons affected with FXS is unknown, however a review of research studies estimated that around 1 in 7,000 males and 1 in 11,000 females had FXS.

Prenatal testing with chorionic villus sample or amniocentesis detects FMR1 mutations while the fetus is still in the womb and looks to be reliable.