Context: Premature ovarian failure (POF) is a cause of female infertility characterized by primary (PA) or secondary amenorrhea (SA) and elevated gonadotropins. The pathogenesis is unknown in most cases. We recently reported two sisters with PA carrying a heterozygous mutation of BMP15 gene (locus Xp11.2), but the prevalence of BMP15 variations in the POF population is unknown. Objective: The objective of the study was to verify the involvement of BMP15 variations in a large POF population. Design and Subjects: Genetic screening of 166 unrelated patients with idiopathic POF (25 PA, 141 SA) and controls (group A: 95 women with menopause beyond 50 yr of age; group B: 86 women and 30 men from the general population) of Caucasian origin. Results: Investigation revealed four heterozygous variations affecting the proregion of BMP15. The previously reported p.Y235C mutation occurred in one and three novel variants in eight patients: two missense alterations (p.R68W in one case, p.A180T in five) and one insertion (p.262insLeu) in two cases. The p.262insLeu was found in five controls of group A, thus diminishing its potential biological impact, whereas the other three variants were not present in any of the controls. All new mutations were found in SA cases. Conclusion: We describe the significant association of heterozygous BMP15 gene variants with the POF phenotype in humans (seven of 166 patients: 4.2%; P < 0.003 vs. controls). These findings are consistent with the critical role played by BMP15 in human folliculogenesis.

BACKGROUND: Studies attempting to precisely define the range of fragile mental retardation 1 (FMR1) expansions and its inf luence in premature ovarian failure (POF) manifestation are partially lacking. To this aim, we evaluated a large cohort of POF patients for the size and, in selected cases, for the sequence of the CGG expansion. Furthermore, the correlation between POF and X-inactivation was investigated in FRAXA families. METHODS: By fluorescent PCR, 190 POF and 200 control women were sized for the CGG tract; some subjects were also characterized by sequencing and for the FMR1 activation ratio. RESULTS AND CONCLUSION: We found a significant association (19/190, 10%, P < 1 × 10⁻⁶) between POF and FMR1 premutation (range 63–163 repeats) and a significant enrichment (9/190, 4.7%, P = 0.021) of POF carriers of intermediate expansions (range 41–58 repeats). Interestingly, intermediate alleles were entirely composed of CGG repeats. Furthermore, the analysis of three pairs of siblings with similar FMR1 expansions and discordant for the POF phenotype showed a direct correlation between the expression of the intermediate/premutated allele and POF manifestation. The results obtained strengthen the correlation between FMR1 expansion and POF and suggest that the manifestation of the ovarian dysfunction could be influenced both by the pattern of interruption of the CGG repeat and by X-inactivation.

Bone morphogenetic protein‐15 (BMP15) is selectively synthesized by oocytes as a pre‐proprotein and is considered an ovarian follicle organizer whose adequate function is critical for female fertility. Missense mutations were reported in primary ovarian insufficiency (POI) but their biological impact remained unexplored. Here, screening of 300 unrelated idiopathic overt POI women with primary or secondary amenorrhea (SA) led to the identification of six heterozygous BMP15 variations in 29 of them. All alterations are nonconservative and include one insertion of three nucleotides (p.L262_L263insL) and five missense substitutions. Except for the p.S5R located in the signal sequence, the other variants (p.R68W, p.R138H, p.L148P, and p.A180T) localize in the proregion, which is essential for the processing and secretion of bioactive dimers. The mutations p.R68W, p.L148P, and the novel p.R138H lead to marked reductions of mature protein production. Their biological effects, evaluated by a novel luciferase‐reporter assay in a human granulosa cell (GC) line, were significantly reduced. Cotransfection experiments of defective mutants with equal amounts of wild‐type BMP15 cDNA, thus reproducing the heterozygous state seen in patients, did not generate a complete recovery of wild‐type activity. No or minor deleterious effects were detected for the variants p.L262_L263insL, p.A180T, or p.S5R. In conclusion, heterozygous BMP15 mutations associated with the early onset of overt POI lead to defective secretion of bioactive dimers. These findings support the concept that an adequate amount of BMP15 secreted in the follicular fluid is critical for female fertility. We propose to consider the screening of BMP15 mutations among the analyses for the prediction of POI risk. Hum Mutat 0, 1–7, 2009.

A total of 106 women affected by premature ovarian failure (POF) were evaluated for fragile X (FRAXA) premutation. The POF patients were classified as having a familial condition (33 women), at least one relative with early menopause (12 women), or a sporadic condition (61 women). The FRAXA premutation was only detected in patients with familial (four out of 33) or sporadic POF (two out of 61). In general, the results obtained indicated that the prevalence [six out of 106, 6%, 95% confidence interval (CI) 3–11%] of FRAXA premutation is significantly higher in women affected by POF than expected (P = 1.24×10^–3), suggesting a phenotype consequence of the premutation alleles. This relationship is more convincingly derived from the observation in two analysed pedigrees of a co-segregation between FRAXA and POF. These findings suggest a possible involvement of premutated alleles in ovarian failure, and indicate the utility of POF families screening for FRAXA premutation in order to prevent the transmission of mental retardation syndrome.

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant neuromuscular disorder associated with the partial deletion of integral numbers of 3.3 kb D4Z4 DNA repeats within the subtelomere of chromosome 4q. A number of candidate FSHD genes, adenine nucleotide translocator 1 gene (ANT1), FSHD-related gene 1 (FRG1), FRG2 and DUX4c, upstream of the D4Z4 array (FSHD locus), and double homeobox chromosome 4 (DUX4) within the repeat itself, are upregulated in some patients, thus suggesting an underlying perturbation of the chromatin structure. Furthermore, a mouse model overexpressing FRG1 has been generated, displaying skeletal muscle defects.