DNA analysis is the method of choice if one is testing specifically for fragile X syndrome and associated trinucleotide repeat expansion in the FMR1 gene.
What tests are done for fragile X syndrome?
The FMR1 DNA test (sometimes called the Fragile X DNA test) thus replaced chromosome testing and became the standard of care for determining the presence of Fragile X. DNA testing detects more than 99% of individuals (both males and females) with FXS, as well as Fragile X carriers.
What type of mutation is fragile X syndrome?
Fragile X syndrome is a genetic disorder which occurs as a result of a mutation of the fragile X mental retardation 1 (FMR1) gene on the X chromosome, most commonly an increase in the number of CGG trinucleotide repeats in the 5′ untranslated region of FMR1.
Can you test for Fragile X in the womb?
The fragile X gene can be detected during pregnancy, but even if the test shows the mutation, it’s impossible to know which, if any, symptoms a child will have or how severe they will be. Chorionic villus sampling (CVS) — this test is usually done between weeks 10 and 12 of the pregnancy.