| The loss-of-function mutation of the FMR1 gene due to expansion of the 5' UTR CGG repeat causes the fragile X syndrome, the most frequent form of inherited mental retardation. On the other hand, the FMR1 premutation, which is transcriptionally active and produces the protein, confers an increased risk for premature ovarian failure (POF) to carrier females. Among 41 unrelated Brazilian women with idiopathic POF, we found three carriers of premutations (CGG expansionse > 59 repeats) and two carriers of high-intermediate alleles (50-55 repeats). Two premutations and two intermediate alleles were detected among the 16 familial POF cases, and one premutated woman, among the 25 sporadic cases. The premutation frequency among the familial cases (12.5%)... |
