Chromosomal abnormalities in women with premature ovarian failure

Histone demethylase KDM4A and KDM4B expression in granulosa cells from women undergoing in vitro fertilization

PURPOSE

To assess expression of the histone demethylases KDM4A and KDM4B in granulosa collected from women undergoing oocyte retrieval and to determine if expression was related to pregnancy outcome.

METHODS

Cumulus and mural granulosa cells were obtained from women undergoing oocyte retrieval. KDM4A and KDM4B mRNA expression was determined by qRT-PCR. KDM4A and KDM4B proteins were immunohistochemically localized in ovarian tissue sections obtained from archival specimens.

RESULTS

KDM4A and KDM4B protein was localized to oocytes, granulosa cells, and theca and luteal cells in ovaries from reproductive-aged women. KDM4A and KDM4B mRNA expression was overall higher in cumulus compared to mural granulosa. When comparing granulosa demethylase gene expression, KDM4A and KDM4B mRNA expression was higher in both cumulus and mural granulosa from not pregnant patients compared to patients in the pregnant-live birth group.

CONCLUSIONS

Histone demethylases KDM4A and KDM4B mRNA are differentially expressed in cumulus and mural granulosa. Expression of both KDM4A and KDM4B mRNA was lower in cumulus granulosa and mural granulosa from pregnant compared to not pregnant patients. These findings suggest that altered expression of histone demethylases may impact epigenetic changes in granulosa cells associated with pregnancy.

A Novel Missense Mutation in the CLPP Gene Causing Perrault Syndrome Type 3 in a Turkish Family

Perrault syndrome (PRLTS) is a heterogeneous group of clinical and genetic disorders characterized by sensory neuronal hearing loss in both sexes and premature ovarian failure or infertility in females. Neurological and hearing loss symptoms appear early in life, but female infertility cannot be detected before puberty. Spastic limbs, muscle weakness, delayed puberty and irregular menstrual cycles have also been observed in PRLTS patients. Mutations in five genes, i.e. HSD17B4, HARS2, CLPP, LARS2, and C10orf2, have been reported in five subtypes of PRLTS. Here, we report a milder phenotype of PRLTS in a Turkish family in which two affected patients had no neurological findings. However, both were characterized by sensory neuronal hearing loss and the female sibling had secondary amenorrhea and gonadal dysgenesis. Genome-wide homozygosity mapping using 300K single-nucleotide polymorphism microarray analysis together with iScan platform (Illumina, USA) followed by candidate gene Sanger sequencing with ABI 3500 Genetic Analyzer (Life Technologies, USA) were used for molecular diagnosis. We found a novel missense alteration c.624C>G; p.Ile208Met in exon 5 of the CLPP at chromosome 19p13.3. This study expands the mutation spectrum of CLPP pathogenicity in PRLTS type 3 phenotype.

Transcription factor SOHLH1 potentially associated with primary ovarian insufficiency

OBJECTIVE

To investigate whether gene variants of SOHLH1 exist in Chinese and Serbian patients with primary ovarian insufficiency (POI).

DESIGN

Case-control genetic study.

SETTING

University hospitals.

PATIENT(S)

A total of 364 Han Chinese and 197 Serbian women with nonsyndromic POI and ethnically matched controls.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

SOHLH1 gene sequencing.

RESULT(S)

We found 10 novel heterozygous variants in our cohorts of 561 women with POI but none in the 600 ethnically matched controls. Statistical and bioinformatic analyses indicated that three of the eight variants in Chinese POI cases are potentially disease causing. They comprise two missense variants (p.Ser317Phe and p.Glu376Lys) that might each change activity of the SOHLH1 protein as a transcription factor and one variant (c.*118C>T) located in the 3' untranslated region of the SOHLH1 gene, which might generate a new binding site for the microRNA hsa-miR-888-5p. Of the two variants in the Serbian POI cases, both were synonymous, and no missense variant was identified. The allele frequencies of some known single-nucleotide polymorphisms were statistically significantly different between patients and controls in both the Chinese and Serbian groups.

CONCLUSION(S)

Our results suggest that SOHLH1 may be regarded as a new candidate gene for POI.

Cytogenetic analysis of 179 Iranian women with premature ovarian failure

The importance of chromosomal abnormalities in etiology of premature ovarian failure (POF) is well known but in many cases, POF still remains idiopathic. We investigated the frequency and type of chromosomal aberrations in Iranian women diagnosed with idiopathic POF. Standard cytogenetic analysis was carried out in a total of 179 patients. Karyotype analysis of these patients revealed that 161 (89.95%) patients had normal female karyotype and 18 (10.05%) patients had abnormal karyotypes. The abnormal karyotypes included sex reverse sex determining region Y (SRY) negative (five Cases), X chromosome mosaicism (five cases), abnormal X chromosomes (three cases), abnormal autosomes (three cases) and X-autosome translocation (two cases). The overall prevalence of chromosomal abnormalities was 10.05% in this first large-scale report of chromosomal aberrations in Iranian women with POF. The results confirm previous observations and emphasis on the critical role of X chromosome abnormalities as one of the possible etiologies for POF.