Reproductive Health of Adolescent Girls Who Carry the FMR1 Premutation
The fragile X mental retardation 1 (FMR1) gene, located on the X chromosome, is characterized by a dynamic CGG repeat expansion in the 5? untranslated region. It has long been known that female carriers of the FMR1 premutation allele (55199 CGG) are at risk for passing the FMR1 full mutation (?200 repeats) to their offspring, which results in a common form of mental retardation known as fragile X syndrome. The FMR1 premutation allele, however, also places female carriers at significantly increased risk for prematurely diminished ovarian function, which we refer to as fragile Xassociated primary ovarian insufficiency (FXPOI). Although of particular concern for younger women, to date, studies of FXPOI have been restricted to women ?18years of age and have not specifically addressed ovarian reserve and menstrual cycle characteristics among adolescent carriers. We discuss the expected reproductive phenotype among FMR1 premutation carriers during adolescence, the associated health considerations based on our current understanding of FXPOI, and the directions for future studies.
reproductive health adolescence fmr1 fragile x syndrome primary ovarian insufficiency fraxa premature ovarian failure premature ovarian insufficiency