Fragile X premutations are not a major cause of early menopause

Fragile X syndrome is an X-linked mental retardation condition that usually is due to a trinucleotide-repeat expansion in the FMR1 gene. Whereas full-mutation al-leles (1230 repeats) lead to fragile X syndrome, pre-mutation alleles (∼60–200 repeats) are apparently non-penetrant. However, previous studies have suggested that female premutation carriers may have an increased incidence of premature menopause. To test this possible association, we screened for premutation alleles among 216 women with early menopause (at age!47 years), 33 of whom had premature menopause (at age!40 years), as well as among 107 control women, all of whom were ascertained solely on the basis of age at menopause. No full-mutation alleles were found; and only one premutation allele was found, but, it was in