A missense in HSF2BP causing primary ovarian insufficiency affects meiotic recombination by its novel interactor C19ORF57/BRME1

Primary Ovarian Insufficiency (POI) is a major cause of infertility, but its etiology remains poorly understood. Using whole-exome sequencing in a family with three cases of POI, we identified the candidate missense variant S167L in HSF2BP, an essential meiotic gene. Functional analysis of the HSF2BP-S167L variant in mouse showed that it behaves as a hypomorphic allele compared to a new loss-of-function (knock-out) mouse model. Hsf2bpS167L/S167L females show reduced fertility with smaller litter sizes. To obtain mechanistic insights, we identified C19ORF57/BRME1 as a strong interactor and stabilizer of HSF2BP and showed that the BRME1/HSF2BP protein complex co-immunoprecipitates with BRCA2, RAD51, RPA and PALB2. Meiocytes bearing the HSF2BP-S167L variant showed a strongly decreased staining of both HSF2BP and BRME1 at the recombination nodules and a reduced number of the foci formed by the recombinases RAD51/DMC1, thus leading to a lower frequency of crossovers. Our results provide insights into the molecular mechanism of HSF2BP-S167L in human ovarian insufficiency and sub(in)fertility.

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A missense in HSF2BP causing Primary Ovarian Insufficiency affects meiotic recombination by its novel interactor C19ORF57/MIDAP

10.1101/2020.03.05.978007 ◽

2020 ◽

Cited By ~ 1

Author(s):

Natalia Felipe-Medina ◽

Sandrine Caburet ◽

Fernando Sánchez-Sáez ◽

Yazmine B. Condezo ◽

Dirk de Rooij ◽

...

Keyword(s):

Missense Variant ◽

Primary Ovarian Insufficiency ◽

Dna Breaks ◽

Ovarian Insufficiency ◽

Knock Out ◽

Recombination Nodules ◽

Meiotic Gene ◽

Double Strand Dna Breaks ◽

Gene Functional Analysis

AbstractPrimary Ovarian Insufficiency (POI) is a major cause of infertility, but its etiology remains poorly understood. Using whole-exome sequencing in a family with 3 cases of POI, we identified the candidate missense variant S167L in HSF2BP, an essential meiotic gene. Functional analysis of the HSF2BP-S167L variant in mouse, compared to a new HSF2BP knock-out mouse showed that it behaves as a hypomorphic allele. HSF2BP-S167L females show reduced fertility with small litter sizes. To obtain mechanistic insights, we identified C19ORF57/MIDAP as a strong interactor and stabilizer of HSF2BP by forming a higher-order macromolecular structure involving BRCA2, RAD51, RPA and PALB2. Meiocytes bearing the HSF2BP-S167L mutation showed a strongly decreased expression of both MIDAP and HSF2BP at the recombination nodules. Although HSF2BP-S167L does not affect heterodimerization between HSF2BP and MIDAP, it promotes a lower expression of both proteins and a less proficient activity in replacing RPA by the recombinases RAD51/DMC1, thus leading to a lower frequency of cross-overs. Our results provide insights into the molecular mechanism of two novel actors of meiosis underlying non-syndromic ovarian insufficiency.SummaryFelipe-Medina et al. describe a missense variant in the meiotic gene HSF2BP in a consanguineous family with Premature Ovarian Insufficiency, and characterize it as an hypormorphic allele, that in vivo impairs its dimerization with a novel meiotic actor, MIDAP/ C19ORF57, and affect recombination at double-strand DNA breaks.

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Biallelic loss of function variants in STAG3 result in primary ovarian insufficiency

Reproductive BioMedicine Online ◽

10.1016/j.rbmo.2021.07.003 ◽

2021 ◽

Author(s):

Leigh A.M. Demain ◽

Eline Boetje ◽

Jonathan J. Edgerley ◽

Emma Miles ◽

Cheryl T. Fitzgerald ◽

...

Keyword(s):

Primary Ovarian Insufficiency ◽

Loss Of Function ◽

Ovarian Insufficiency

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A hypomorphic allele of SLC35D1 results in Schneckenbecken-like dysplasia

Human Molecular Genetics ◽

10.1093/hmg/ddz200 ◽

2019 ◽

Vol 28 (21) ◽

pp. 3543-3551

Author(s):

Carsten Rautengarten ◽

Oliver W Quarrell ◽

Karen Stals ◽

Richard C Caswell ◽

Elisa De Franco ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Missense Variant ◽

Sugar Transporter ◽

Loss Of Function ◽

Transport Activity ◽

Nucleotide Sugar ◽

Gene Encoding ◽

Hypomorphic Allele ◽

Nucleotide Sugar Transporter

Abstract We report the case of a consanguineous couple who lost four pregnancies associated with skeletal dysplasia. Radiological examination of one fetus was inconclusive. Parental exome sequencing showed that both parents were heterozygous for a novel missense variant, p.(Pro133Leu), in the SLC35D1 gene encoding a nucleotide sugar transporter. The affected fetus was homozygous for the variant. The radiological features were reviewed, and being similar, but atypical, the phenotype was classified as a ‘Schneckenbecken-like dysplasia.’ The effect of the missense change was assessed using protein modelling techniques and indicated alterations in the mouth of the solute channel. A detailed biochemical investigation of SLC35D1 transport function and that of the missense variant p.(Pro133Leu) revealed that SLC35D1 acts as a general UDP-sugar transporter and that the p.(Pro133Leu) mutation resulted in a significant decrease in transport activity. The reduced transport activity observed for p.(Pro133Leu) was contrasted with in vitro activity for SLC35D1 p.(Thr65Pro), the loss-of-function mutation was associated with Schneckenbecken dysplasia. The functional classification of SLC35D1 as a general nucleotide sugar transporter of the endoplasmic reticulum suggests an expanded role for this transporter beyond chondroitin sulfate biosynthesis to a variety of important glycosylation reactions occurring in the endoplasmic reticulum.

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Primary aldosteronism associated with a germline variant in CACNA1H

BMJ Case Reports ◽

10.1136/bcr-2018-229031 ◽

2019 ◽

Vol 12 (5) ◽

pp. e229031 ◽

Cited By ~ 1

Author(s):

Kendra Wulczyn ◽

Edward Perez-Reyes ◽

Robert L Nussbaum ◽

Meyeon Park

Keyword(s):

Primary Aldosteronism ◽

De Novo ◽

Missense Variant ◽

Laboratory Evaluation ◽

Loss Of Function ◽

Aldosterone Secretion ◽

Whole Exome ◽

Voltage Dependent ◽

Cell Current ◽

Voltage Sensing Domain

The CACNA1H gene encodes the pore-forming α1 subunit of the T-type voltage-dependent calcium channel CaV3.2, expressed abundantly in the adrenal cortex. Mutations in CACNA1H are associated with various forms of primary aldosteronism (PA), including familial hyperaldosteronism type 4 (FH4). We describe a patient with refractory hypokalaemia and elevated aldosterone secretion independent of renin activity. Despite the absence of overt hypertension in this patient, the laboratory evaluation was consistent with a diagnosis of PA. Whole-exome sequencing revealed a de novo missense variant, R890H, in the voltage sensing domain of CACNA1H. Expression of the variant channel in cells resulted in decreased whole-cell current, consistent with a loss-of-function. We hypothesise this variant is the genetic cause of pathological aldosterone secretion in this patient, and thereby expand the current understanding of the genetic basis of FH4.

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OR31-06 Candidate Gene Variants in a Large Cohort of Women with Primary Ovarian Insufficiency

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.1419 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Bushra Gorsi ◽

Mika Moriwaki ◽

Marvin B Moore ◽

Aleksandar Rajkovic ◽

Lawrence M Nelson ◽

...

Keyword(s):

Functional Model ◽

Primary Ovarian Insufficiency ◽

Composite Likelihood ◽

Large Cohort ◽

Gene Variants ◽

Loss Of Function ◽

Test Statistic ◽

Ovarian Insufficiency ◽

Total N

Abstract Primary ovarian insufficiency (POI) is highly heritable. The majority of cases have no known cause. We hypothesized that mutations in previously identified genes or genes from the same pathways are the cause of POI in a recessive or dominant manner. Subjects included 294 women diagnosed with POI (amenorrhea with an elevated FSH level). All had a 46XX karyotype, and normal FMR1 repeat number. Subjects were recruited in Boston (n=95), at the NIH and Washington University (n=98), and in Pittsburgh (n=98). Controls included subjects recruited for health in old age and disorders unrelated to reproduction or cancer, and subjects from the 1000 Genomes Project (total n=587). Variants were called using the Sentieon software package (https://www.sentieon.com). Case and control samples were stratified on ethnicity, relatedness and heterozygosity. Peddy and XPAT were used to calculate quality control metrics to detect outlier samples for removal from analysis to create a homogenous dataset. The number of cases (227) and controls (458) was adjusted for downstream analysis. XPAT imposed additional quality filters and removed variants. A second filter removed variants that did not pass a Gnomad filter of <0.001 allele frequency. VAAST was used to determine a composite likelihood ratio (CLR) as the test statistic to represent the aggregate burden of variants of affected individuals in each transcript relative to a set of 458 control genomes. The significance of each transcript’s VAAST CLR score was evaluated by 1 million permutations. We screened exomes for variants in previously identified genes causing POI in humans and those demonstrating infertility in a male or female mouse model. We also used the American College of Medical Genetics and Genomics standards for interpretation of pathogenicity of a variant, with priority on null variants in genes with probability of loss of function intolerance based on the observed vs. expected rate in gnomAD, in vivo or in vitro functional evidence of a damaging effect, significantly increased prevalence compared to controls, i.e. not found in any controls or in fewer than 10 in the gnomAD database if the subject had a matching race/ethnicity. Thirty-four subjects were removed for poor quality exomes and relatedness. Fifty-three subjects had at least one variant in a previously identified POI gene or one in which there was a previously identified functional model. Two subjects carried recessive variants and 30 carried at least one novel heterozygous candidate variant for follow up. Analysis of genetic causes of POI in this large cohort identified candidate causal gene variants in over half of the subjects. The data demonstrate that the genetic architecture is heterogeneous. Although recessive mutations have been identified in consanguineous families, the data suggest that a dominant or oligogenic pattern of inheritance may be important.

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Heterozygous FMN2 Missense Variant Found in A Family Case of Premature Ovarian Insufficiency

10.21203/rs.3.rs-832452/v1 ◽

2021 ◽

Author(s):

Jie Li ◽

Tianliu Peng ◽

Le Wang ◽

Panpan Long ◽

Ruping Quan ◽

...

Keyword(s):

Exome Sequencing ◽

Low Frequency ◽

Missense Variant ◽

Sporadic Case ◽

Premature Ovarian Insufficiency ◽

Chinese Family ◽

Ovarian Insufficiency ◽

Mutant Type ◽

Pathogenic Genes ◽

Whole Exome

Abstract Background Premature Ovarian Insufficiency plagues 1% of women under 40, while quite a few remain an unknown cause. The development of sequencing has helped find pathogenic genes and reveal the relationship between DNA repair and ovarian reserve. Through the exome sequencing, our study targets screening out the possible POI pathogenic gene and variants in a Chinese family and 20 sporadic POI patients, preliminarily exploring the functional impact and finding out potential linkages between the gene and POI. Results The whole exome sequencing suggested a novel FMN2 heterozygous variant c.1949C > T (p.Ser650Leu) carried by all three patients in a Chinese family and another c.1967G > A(p.Arg656His) variant in a sporadic case. Since no FMN2 missense mutation is reported for causing human POI, we preliminarily assessed p.Ser650Leu variant via cross-species alignment and 3D modeling and found it possibly deleterious. A series of functional evidence was consistent with our hypothesis. We proved the expression of FMN2 in different stages of oocytes and observed a statistical difference of chromosomal breakages between the POI patient carrying p.Arg656His variant and the health control (p = 0.0013). Western Blot also suggested a decrease in FMN2 and P21 in the mutant type and an associated increase in H2AX. The p.Arg656His variant with an extremely low frequency also indicated that the gene FMN2 might play an essential role in the genetic etiology of POI. To the best of our knowledge, this is the first POI report on missense variants of FMN2. Conclusion This finding indicates a novel gene possibly related to POI and sheds lights on the study of FMN2.

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A homozygous hypomorphic BRCA2 variant causes primary ovarian insufficiency without cancer or Fanconi anemia traits

10.1101/751644 ◽

2019 ◽

Cited By ~ 2

Author(s):

Sandrine Caburet ◽

Abdelkader Heddar ◽

Elodie Dardillac ◽

Helene Creux ◽

Marie Lambert ◽

...

Keyword(s):

Fanconi Anemia ◽

Missense Variant ◽

Strand Break ◽

Primary Ovarian Insufficiency ◽

Ovarian Insufficiency ◽

Her Family ◽

Major Player ◽

Chromosomal Breaks ◽

Turkish Family ◽

Radiation Induced

ABSTRACTPrimary Ovarian insufficiency (POI) affects 1% of women under forty. We studied a patient with a non-syndromic POI, from a consanguineous Turkish family. Exome sequencing identified a homozygous missense variant c.8524C>T/p.R2842C in BRCA2. BRCA2 is a major player in homologous recombination (HR). BRCA2 deficiency induces cancer predisposition and Fanconi Anemia (FA). Remarkably, neither the patient nor her family exhibit somatic pathologies. The patient’s somatic cells presented intermediate levels of chromosomal breaks, cell proliferation and radiation-induced RAD51 foci formation when compared to controls, the heterozygous mother’s and FA cells. R2842C-BRCA2 partially complemented BRCA2 depletion for double-strand break-induced HR. The residual HR function in patient’s cells could explain the absence of somatic pathology. BRCA2 is expressed in human fetal ovaries in pachytene stage oocytes, when meiotic HR occurs. This study has a major impact on the understanding of genome maintenance in somatic and meiotic cells and on the management of POI patients.

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STAG3 homozygous missense variant causes primary ovarian insufficiency and male non-obstructive azoospermia

MHR Basic science of reproductive medicine ◽

10.1093/molehr/gaaa050 ◽

2020 ◽

Vol 26 (9) ◽

pp. 665-677

Author(s):

Sylvie Jaillard ◽

Kenneth McElreavy ◽

Gorjana Robevska ◽

Linda Akloul ◽

Farah Ghieh ◽

...

Keyword(s):

Dna Sequences ◽

Genetic Basis ◽

Missense Variant ◽

Reproductive Organs ◽

Female Infertility ◽

Obstructive Azoospermia ◽

Ovarian Insufficiency ◽

Male And Female ◽

Whole Exome ◽

Pathological Development

Abstract Infertility, a global problem affecting up to 15% of couples, can have varied causes ranging from natural ageing to the pathological development or function of the reproductive organs. One form of female infertility is premature ovarian insufficiency (POI), affecting up to 1 in 100 women and characterised by amenorrhoea and elevated FSH before the age of 40. POI can have a genetic basis, with over 50 causative genes identified. Non-obstructive azoospermia (NOA), a form of male infertility characterised by the absence of sperm in semen, has an incidence of 1% and is similarly heterogeneous. The genetic basis of male and female infertility is poorly understood with the majority of cases having no known cause. Here, we study a case of familial infertility including a proband with POI and her brother with NOA. We performed whole-exome sequencing (WES) and identified a homozygous STAG3 missense variant that segregated with infertility. STAG3 encodes a component of the meiosis cohesin complex required for sister chromatid separation. We report the first pathogenic homozygous missense variant in STAG3 and the first STAG3 variant associated with both male and female infertility. We also demonstrate limitations of WES for the analysis of homologous DNA sequences, with this variant being ambiguous or missed by independent WES protocols and its homozygosity only being established via long-range nested PCR.

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