Association of FOXD1 variants with adverse pregnancy outcomes in mice and humans.

Recurrent spontaneous abortion (RSA) is a common cause of infertility, but previous attempts at identifying RSA causative genes have been relatively unsuccessful. Such failure to describe RSA aetiological genes might be explained by the fact that reproductive phenotypes should be considered as quantitative traits resulting from the intricate interaction of numerous genetic, epigenetic and environmental factors. Here, we studied an interspecific recombinant congenic strain (IRCS) of Mus musculus from the C57BL6/J strain of mice harbouring an approximate 5 Mb DNA fragment from chromosome 13 from Mus spretus mice (66H-MMU13 strain), with a high rate of embryonic resorption (ER). Transcriptome analyses of endometrial and placental tissues from these mice showed a deregulation of many genes associated with the coagulation and inflammatory response pathways. Bioinformatics approaches led us to select Foxd1 as a candidate gene potentially related to ER and RSA. Sequencing analysis of Foxd1 in the 66H-MMU13 strain, and in 556 women affected by RSA and 271 controls revealed non-synonymous sequence variants. In vitro assays revealed that some led to perturbations in FOXD1 transactivation properties on promoters of genes having key roles during implantation/placentation, suggesting a role of this gene in mammalian implantation processes.

Analysis of FMR1 gene premutation and X chromosome cytogenetic abnormalities in 100 Tunisian patients presenting premature ovarian failure.

OBJECTIVE: To evaluate the prevalence of FMR1 premutations and X chromosome cytogenetic abnormalities in a large cohort of Tunisian women with premature ovarian failure (POF). PATIENTS AND METHODS: The cohort consisted of 127 Tunisian women with POF referred by endocrinologists and gynecologists for genetic investigation in the context of idiopathic POF and altered hormonal profiles. Clinical information concerning the reproductive function in the family, previous hormonal measurements and/or possible fertility treatment were collected. Karyotype, FISH analyses, FMR1 and FMR2 testing were performed for all patients. RESULTS: Fifteen patients (11.81%) presented structural or numerical X chromosomal abnormalities. Moreover, we detected in 12 patients (10.71%) a high level of X mosaicism. Analysis of FMR1 gene in the 100 patients without X chromosomal abnormalities showed that five percent of the patients carried a FMR1 premutation allele. On the other hand, the FMR2 screening did not reveal any deletion. CONCLUSION: Our study confirms the major role of X chromosome abnormalities in POF and highlights the importance of karyotype analyses and FMR1 screening. These investigations provide valuable information for diagnosis and genetic counseling for these women who still have a 5% chance of spontaneous conception.

NR5A1 (SF-1) gene variants in a group of 26 young women with XX primary ovarian insufficiency.

OBJECTIVE: To determine whether NR5A1 (SF-1) variants are a cause of primary ovarian insufficiency (POI) in 26 young women with similar genetic background. DESIGN: Genetic and functional mutation study. SETTING: University hospitals. PATIENT(S): Genetic analysis of the NR5A1 gene in 26 XX girls with POI. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): NR5A1 molecular and functional analysis. RESULT(S): Genetic analysis revealed a new c.763C>T (p.Arg255Cys) mutation and a recurrent c.437G>C (p.Gly146Ala) variant. Functional analysis of the p.Arg255Cys mutant showed a marked decrease in transactivation on the Cyp11a1 and Amh promoters. The p.Gly146Ala variant was identified significantly more often in the patients (46.1%) than in ancestry-matched control subjects (10%). CONCLUSION(S): We identified one new NR5A1 mutation in a patient of our POI cohort (prevalence 3.8%). Moreover, although our study is limited in the number of cases, we report the high frequency of the p.Gly146Ala variant in this cohort compared with the ancestry-matched control subjects. This work highlights the important role of SF-1 in ovarian function.

Mutational screening of SF1 and WNT4 in Tunisian women with premature ovarian failure.

BACKGROUND: WNT4 and SF1 genes play an important role in ovarian development. They constitute coherent candidate genes associated with premature ovarian failure (POF) pathogenesis. METHODS: We sequenced the coding region of WNT4 and SF1 in 55 Tunisian women with POF and 100 healthy controls. RESULTS: We identified a synonymous variation in WNT4 (c.99G>A, p.Ser33Ser) and a substitution (c.G437C) in SF1 gene inducing G146 to Ala (GGG-GCG) missense mutation. WNT4 (c.99G>A, p.Ser33Ser) was not associated with POF pathology. However, a positive association of SF1 Gly146Ala polymorphism was noted. Gly146Ala minor allele frequency was significantly higher (p=0.029) in POF patients versus controls and Ala allele containing genotypes (p=0.005) were positively associated with POF pathology. The carriage of 146Ala allele was also associated with a significant reduction in estradiol plasma levels. CONCLUSIONS: SF1 Gly146Ala polymorphism seems to be associated with POF pathology in the Tunisian population likely by reducing estradiol levels.

CITED2 mutations potentially cause idiopathic premature ovarian failure.

Anomalies in gonadal development in a mouse knockout model of Cited2 have been recently described. In Cited2(-/-) female gonads, an ectopic cell migration was observed and the female program of sex determination was transiently delayed. We hypothesize that, in humans, this temporary inhibition of genes should be sufficient to provoke a developmental impairment of the female gonads, conducive to premature ovarian failure (POF). To establish whether CITED2 mutations are a common cause of the disease, we performed a mutational analysis of this gene in a panel of patients with POF and in a group of control women with normal fertility. We amplified and directly sequenced the complete open reading frame of CITED2 in 139 patients with POF and 290 controls. This study revealed 5 synonymous and 3 nonsynonymous variants. Among these, 7 are novel. The nonsynonymous variant c.604C>A (p.Pro202Thr) was found uniquely in 1 woman from the POF group. In silico analysis of this mutation indicated a potential deleterious effect. We conclude that mutations in CITED2 may be involved in POF pathogenesis.

Screening for mutations of the FOXO4 gene in premature ovarian failure patients.

FOXO4 constitutes a coherent candidate gene associated with premature ovarian failure (POF) pathogenesis. This study sequenced the coding and exon-flanking regions of this gene in a panel of 116 POF patients and 143 controls of Tunisian origin. In both groups, the IVS2 + 41T > G sequence variant was identified. It is concluded that coding mutations of FOXO4 should not be a common cause of the disease in women from the Tunisian population. However, this study cannot exclude that FOXO4 dysfunctions, originated from open reading frame or promoter sequence variations, might be associated with the pathogenesis of the disease in other ethnical groups.

Sequence analysis of the CDKN1B gene in patients with premature ovarian failure reveals a novel mutation potentially related to the phenotype.

Earlier reports demonstrated a key role of Cdkn1b during mouse ovarian development. In this study, the sequencing analysis of the complete coding region of this gene in a panel of premature ovarian failure patients and control subjects reveals a novel mutation potentially related to the phenotype.