Exome sequencing in 16 patients with pituitary stalk interruption syndrome: A monocentric study.

Pituitary stalk interruption syndrome (PSIS) is a rare disorder characterized by an absent or ectopic posterior pituitary, absent or interrupted pituitary stalk and anterior pituitary hypoplasia on magnetic resonance imaging (MRI), as well in some cases a range of heterogeneous somatic anomalies. The triad can be incomplete. Here, we performed exome sequencing on 16 sporadic patients, aged 0.4 to 13.7 years diagnosed with isolated or complex PSIS. Growth hormone deficiency was isolated in 10 cases, or associated with thyrotropin deficiency in 6 others (isolated (2 cases), associated with adrenocorticotropin deficiency (1 case), gonadotropins deficiency (1 case), or multiple deficiencies (2 cases)). Additional phenotypic anomalies were present in six cases (37.5%) including four with ophthalmic disorders. In 13 patients variants were identified that may contribute to the phenotype. However, only a single individual carried a variant classified as pathogenic. This child presented with the typical clinical presentation of Okur-Chung neurodevelopmental syndrome due to a CSNK2A1 missense variant. We also identified variants in the holoprosencephaly associated genes GLI2 and PTCH1. A likely pathogenic novel splice site variant in the GLI2 gene was observed in a child with PSIS and megacisterna magna. In the remaining 11 cases 26 variants in genes associated with pituitary development or function were identified and were classified of unknown significance. Compared with syndromic forms the diagnostic yield in the isolated forms of PSIS is low. Although we identified rare or novel missense variants in several hypogonadotropic hypogonadism genes (e.g. FGF17, HS6ST1, KISS1R, CHD7, IL17RD) definitively linking them to the PSIS phenotype is premature. A major challenge remains to identify pathogenic variants in cases with isolated PSIS.

Peripheral Precocious Puberty of Ovarian Origin in a Series of 18 Girls: Exome Study Finds Variants in Genes Responsible for Hypogonadotropic Hypogonadism.

Background: Peripheral precocious puberty of ovarian origin is a very rare condition compared to central form. It may be associated with an isolated ovarian cyst (OC). The causes of OC in otherwise healthy prepubertal girls is currently unknown. Methods: Exome sequencing was performed on a cohort of 18 unrelated girls presenting with prenatal and/or prepubertal OC at pelvic ultrasonography. The presenting symptom was prenatal OC in 5, breast development in 7 (with vaginal bleeding in 3) and isolated vaginal bleeding in 6. All had OC ≥ 10 mm. The girls had no other anomalies. Four patients had a familial history of ovarian anomalies and/or infertility. Results: In 9 girls (50%), candidate or known pathogenic variants were identified in genes associated with syndromic and non-syndromic forms of hypogonadotropic hypogonadism including PNPLA6, SEMA3A, TACR3, PROK2, KDM6A, KMT2D, OFD1, GNRH1, GNRHR, GLI3, INSR, CHD7, CDON, RNF216, PROKR2, GLI3, LEPR. Basal plasma concentrations of gonadotropins were undetectable and did not increase after gonadotropin-releasing hormone test in 3 of them whilst 5 had prepubertal values. The plasma estradiol concentrations were prepubertal in 6 girls, high (576 pmol/L) in one and not evaluated in 2 of them. Conclusions: In the first study reporting exome sequencing in prepubertal OC, half of the patients with OC carry either previously reported pathogenic variants or potentially pathogenic variants in genes known to be associated with isolated or syndromic forms of congenital hypogonadotropic hypogonadism. Functional studies and studies of other cohorts are recommended to establish the causality of these variants.

SRY-negative 46,XX testicular/ovotesticular DSD: Long-term outcomes and early blockade of gonadotropic axis.

OBJECTIVE: SRY-negative 46,XX testicular and ovotesticular disorders/differences of sex development (T/OTDSD) represent a very rare and unique DSD condition where testicular tissue develops in the absence of a Y chromosome. To date, very few studies have described the phenotype, clinical and surgical management and long-term outcomes of these patients. Particularly, early blockade of the gonadotropic axis in patients raised in the female gender to minimize postnatal androgenization has never been reported. DESIGN: Retrospective description of sixteen 46,XX T/OTDSD patients. RESULTS: Sixteen 46,XX SRY-negative T/OTDSD were included. Most (12/16) were diagnosed in the neonatal period. Sex of rearing was male for six patients and female for ten, while the clinical presentation varied, with an external masculinization score from 1 to 10. Five patients raised as girl were successfully treated with GnRH analog to avoid virilization during minipuberty. Ovotestes/testes were found bilaterally for 54% of the patients and unilaterally for the others (with a contralateral ovary). Gonadal surgery preserved appropriate tissue in the majority of cases. Spontaneous puberty occurred in two girls and one boy, while two boys required hormonal induction of puberty. One of the girls conceived spontaneously and had an uneventful pregnancy. DNA analyses (SNP-array, next-generation sequencing and whole-exome sequencing) were performed. A heterozygous frameshit mutation in the NR2F2 gene was identified in one patient. CONCLUSIONS: This study presents a population of patients with 46,XX SRY-negative T/OTDSD. Early blockade of gonadotropic axis appears efficient to reduce and avoid further androgenization in patients raised as girls.

Pituitary stalk interruption syndrome is characterized by genetic heterogeneity.

Pituitary stalk interruption syndrome is a rare disorder characterized by an absent or ectopic posterior pituitary, interrupted pituitary stalk and anterior pituitary hypoplasia, as well as in some cases, a range of heterogeneous somatic anomalies. A genetic cause is identified in only around 5% of all cases. Here, we define the genetic variants associated with PSIS followed by the same pediatric endocrinologist. Exome sequencing was performed in 52 (33 boys and 19 girls), including 2 familial cases single center pediatric cases, among them associated 36 (69.2%) had associated symptoms or syndromes. We identified rare and novel variants in genes (37 families with 39 individuals) known to be involved in one or more of the following-midline development and/or pituitary development or function (BMP4, CDON, GLI2, GLI3, HESX1, KIAA0556, LHX9, NKX2-1, PROP1, PTCH1, SHH, TBX19, TGIF1), syndromic and non-syndromic forms of hypogonadotropic hypogonadism (CCDC141, CHD7, FANCA, FANCC, FANCD2, FANCE, FANCG, IL17RD, KISS1R, NSMF, PMM2, SEMA3E, WDR11), syndromic forms of short stature (FGFR3, NBAS, PRMT7, RAF1, SLX4, SMARCA2, SOX11), cerebellum atrophy with optic anomalies (DNMT1, NBAS), axonal migration (ROBO1, SLIT2), and agenesis of the corpus callosum (ARID1B, CC2D2A, CEP120, CSPP1, DHCR7, INPP5E, VPS13B, ZNF423). Pituitary stalk interruption syndrome is characterized by a complex genetic heterogeneity, that reflects a complex phenotypic heterogeneity. Seizures, intellectual disability, micropenis or cryptorchidism, seen at presentation are usually considered as secondary to the pituitary deficiencies. However, this study shows that they are due to specific gene mutations. PSIS should therefore be considered as part of the phenotypic spectrum of other known genetic syndromes rather than as specific clinical entity.

Testis formation in XX individuals resulting from novel pathogenic variants in Wilms' tumor 1 (WT1) gene.

Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor ß-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.

The TALE homeodomain of PBX1 is involved in human primary testis-determination.

Human sex-determination is a poorly understood genetic process, where gonad development depends on a cell fate decision that occurs in a somatic cell to commit to Sertoli (male) or granulosa (female) cells. A lack of testis-determination in the human results in 46,XY gonadal dysgenesis. A minority of these cases is explained by mutations in genes known to be involved in sex-determination. Here, we identified a de novo missense mutation, p.Arg235Gln in the highly conserved TALE homeodomain of the transcription factor Pre-B-Cell Leukemia Transcription Factor 1 (PBX1) in a child with 46,XY gonadal dysgenesis and radiocubital synostosis. This mutation, within the nuclear localization signal of the protein, modifies the ability of the PBX1 protein to localize to the nucleus. The mutation abolishes the physical interaction of PBX1 with two proteins known to be involved in testis-determination, CBX2 and EMX2. These results provide a mechanism whereby this mutation results specifically in the absence of testis-determination.

A Novel Homozygous Missense Mutation in the FU-CRD2 Domain of the R-spondin1 Gene Associated with Familial 46,XX DSD.

R-spondin proteins are secreted agonists of canonical WNT/ß-catenin signaling. Homozygous RSPO1 mutations cause a syndrome of 46,XX disorder of sexual development (DSD), palmoplantar keratoderma (PPK), and predisposition to squamous cell carcinoma. We report exome sequencing data of two 46,XX siblings, one with testicular DSD and the other with suspected ovotesticular DSD. Both have PPK and hearing impairment and carried a novel homozygous mutation c.332G>A (p.Cys111Tyr) located in the highly conserved furin-like cysteine-rich domain-2 (FU-CRD2). Cysteines in the FU-CRDs are strictly conserved, indicating their functional importance in WNT signaling through interaction with the leucine-rich repeat-containing G-protein-coupled receptors. This is the first RSPO1 missense mutation reported in association with human disease.

Mutations in the Human ROBO1 Gene in Pituitary Stalk Interruption Syndrome.

Context: Pituitary stalk interruption syndrome (PSIS) is characterized by a thin or absent pituitary stalk usually in association with an ectopic posterior pituitary and hypoplasia/aplasia of the anterior pituitary. Associated phenotypes include varied ocular anomalies, hypoglycemia, micropenis/cryptorchidism, growth failure, or combined pituitary hormone deficiencies. Although genetic causes have been identified, they explain only around 5% of PSIS cases. Objective: To identify genetic causes of PSIS by exome sequencing. Design: Exon enrichment was performed using the Agilent SureSelect Human All Exon V4. Paired-end sequencing was performed on the Illumina HiSeq2000 platform with an average sequencing coverage of ×50. Patients: Patients with unexplained PSIS were included in the study. Results: In five cases of unexplained PSIS including two familial cases, we identified a novel heterozygous frameshift and nonsense and missense mutations in the ROBO1 gene (p.Ala977Glnfs*40, two affected sibs; p.Tyr1114Ter, sporadic case, and p.Cys240Ser, affected child and paternal aunt) that controls embryonic axon guidance, and branching in the nervous system. Interestingly, four of the five cases of PSIS also presented with ocular anomalies, including hypermetropia with strabismus as well as ptosis. Conclusions: These data suggest that mutations in ROBO1 contribute to PSIS and associated ocular anomalies.

Novel AMH and AMHR2 Mutations in Two Egyptian Families with Persistent Müllerian Duct Syndrome.

Anti-müllerian hormone (AMH) is produced by Sertoli cells and signals through 2 transmembrane receptors (AMHR), specific types I and II, leading to regression of müllerian ducts during fetal male sex differentiation. Mutations in AMH and AMHR2 lead to the persistence of müllerian ducts in males which is transmitted in a recessive pattern. Here, we report 2 Egyptian DSD (disorder of sex development) patients reared as males who presented with bilateral cryptorchidism and otherwise normal male external genitalia and who both had a 46,XY karyotype. The first patient presented at the age of 2 years. Laparoscopic surgery revealed a uterus and fallopian tubes with the presence of 2 gonads, and biopsy and pathology revealed prepubertal testicular tissue showing small-sized tubules with mostly Sertoli cells and very few spermatogonia, edematous stroma, and no detectable ovarian tissue. The second patient presented at the age of 3 years. Laparoscopic surgery revealed a uterus and fallopian tubes, and serum AMH was very low (0.1 ng/mL). Molecular studies revealed a novel missense mutation in the AMHR2 gene in the first patient (c.767A>C; p.H256P) and a novel frameshift mutation in the AMH gene in the second patient (c.203delC; p.L70Cfs*7). We conclude that persistent müllerian ducts should be included in the differential diagnosis of cryptorchidism.

WT1 Gene Mutation, p.R462W, in a 46,XY DSD Patient from Egypt with Gonadoblastoma and Review of the Literature.

WT1 gene mutations have been described in 46,XY patients with ambiguous genitalia or complete gonadal dysgenesis with or without Wilms' tumor, nephropathy, gonadoblastoma, and other defects, e.g., cryptorchidism or hypospadias. p.R462W is a hot spot mutation in exon 9 and is the most common mutation in patients with Denys-Drash syndrome. However, in this study we report an Egyptian patient with a novel phenotype carrying the p.R462W mutation. We also review the heterogeneity of phenotypes of previously reported patients with the p.R462W (previously referred to as Arg394Trp) mutation.

Aromatase Deficiency due to a Homozygous CYP19A1 Mutation in a 46,XX Egyptian Patient with Ambiguous Genitalia.

Aromatase deficiency (AD) is a very rare disorder resulting from mutations in the CYP19A1 gene encoding aromatase, a cytochrome P450 enzyme that plays a pivotal role in androgen conversion to estrogens. AD is inherited in an autosomal recessive trait, and to date only 35 cases have been described in the literature. Herein, we depict a new patient reared as a male, who presented at the age of 21 years with no palpable testis, hypoplastic scrotum, penis-like phallus (3 cm), and penoscrotal hypospadias. The patient was born to consanguineous parents, his karyotype was 46,XX, and SRY was negative. Pelvic sonar showed a small hypoplastic uterus, and no testis could be identified. Serum testosterone was within the reference range of females along with high gonadotropins. Pathology of gonadal biopsy showed ovarian stroma negative for oocytic follicle consistent with streak gonads. All these data were suggestive of AD, which was subsequently confirmed by molecular investigation of the CYP19A1 gene. A homozygous splice site mutation in the donor splice site of exon 9 was identified, c.1263 + 1G>T. This is the first report of such a rare disorder in an Egyptian patient. Our results reinforce the importance of considering AD in patients with 46,XX disorders of sex development after ruling out congenital adrenal hyperplasia.

Familial forms of disorders of sex development may be common if infertility is considered a comorbidity.

BACKGROUND: Families with 46,XY Disorders of Sex Development (DSD) have been reported, but they are considered to be exceptionally rare, with the exception of the familial forms of disorders affecting androgen synthesis or action. The families of some patients with anorchia may include individuals with 46,XY gonadal dysgenesis. We therefore analysed a large series of patients with 46,XY DSD or anorchia for the occurrence in their family of one of these phenotypes and/or ovarian insufficiency and/or infertility and/or cryptorchidism. METHODS: A retrospective study chart review was performed for 114 patients with 46,XY DSD and 26 patients with 46,XY bilateral anorchia examined at a single institution over a 33 year period. RESULTS: Of the 140 patients, 25 probands with DSD belonged to 21 families and 7 with anorchia belonged to 7 families. Familial forms represent 22% (25/114) of the 46,XY DSD and 27% (7/26) of the anorchia cases. No case had disorders affecting androgen synthesis or action or 5 α-reductase deficiency. The presenting symptom was genital ambiguity (n = 12), hypospadias (n = 11) or discordance between 46,XY karyotyping performed in utero to exclude trisomy and female external genitalia (n = 2) or anorchia (n = 7). Other familial affected individuals presented with DSD and/or premature menopause (4 families) or male infertility (4 families) and/or cryptorchidism. In four families mutations were identified in the genes SRY, NR5A1, GATA4 and FOG2/ZFPM2. Surgery discovered dysgerminoma or gonadoblastoma in two cases with gonadal dysgenesis. CONCLUSIONS: This study reveals a surprisingly high frequency of familial forms of 46,XY DSD and anorchia when premature menopause or male factor infertility are included. It also demonstrates the variability of the expression of the phenotype within the families. It highlights the need to the physician to take a full family history including fertility status. This could be important to identify familial cases, understand modes of transmission of the phenotype and eventually understand the genetic factors that are involved.

Genetic mutations and somatic anomalies in association with 46,XY gonadal dysgenesis.

OBJECTIVE: To assess genetic mutations and associated somatic anomalies in a series of patients with 46,XY gonadal dysgenesis (GD). DESIGN: Single center retrospective study. SETTING: University pediatric hospital. PATIENT(S): Fourteen patients with 46,XY GD. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genotype-phenotype relationship. RESULT(S): The presenting symptom was disorders of sex development (6 patients), primary amenorrhea (2 patients), discordance between 46,XY karyotype and female external genitalia (3 patients), discovery of Müllerian structures at surgery (2 patients), or diagnosed in the evaluation of a gonadal tumor (1 patient). Müllerian structures were shown by ultrasound evaluation in 7 of 13 patients, genitography in 3 of 6 patients and/or surgery in 8 of 10 patients (3 not seen at imaging), or only by histologic examination (1 patient). Three patients had gonadoblastoma and/or seminoma. A mutation was found in 7 patients of whom 2 had family history of reproductive problems and 5 had associated somatic anomalies. The mutations were FOG2/ZFPM2 (1 patient), SRY (2 patients), WT1 (1 patient), or deletions of distal chromosome 9p (3 patients). Among the three other patients with associated anomalies and no mutation, two had ectodermal dysplasia and one had leukemia. CONCLUSION(S): Mutations were observed in half of the patients with 46,XY GD with Müllerian structures. We also describe for the first time the association between GD and ectodermal dysplasia. Müllerian structures can be found in some cases only by histologic examination, which should be coupled to preventive gonadectomy because of the risk of tumor formation.

Etiology of primary ovarian insufficiency in a series young girls presenting at a pediatric endocrinology center.

UNLABELLED: The cause of the primary ovarian insufficiency (POI) remains unknown in the majority of cases. A retrospective study was carried out in 17 girls with POI and normal 46,XX karyotype evaluated before 20 years of age. The etiology of POI was determined in eight girls (group 1) and remained idiopathic in nine girls (group 2). In group 1, five patients had a medical history: cerebellar ataxia due to congenital disorder of glycosylation (CDG) 1 in three cases, mitochondrial disease in one case, and autoimmune deficiencies in one case. The diagnosis of POI was made on pubertal delay or primary amenorrhea in these five patients, whilst the others presented with clitoral hypertrophy at birth or short stature and pubertal delay in two cases with NR5A1 mutation or with short stature and learning difficulties in one case with mitochondrial disease. In group 2, associated diseases were arthrogryposis malformative, gut, and bladder malformations and kidney failure or parieto-occipital tumor. The genes tested (NR5A1, BMP15, GDF9, and NOBOX) showed no mutation. CONCLUSIONS: The frequency of defined etiologies (47%) is high. This is probably because of the recruitment of the cases at the pediatric center, where other somatic anomalies can lead to the accurate determination of the etiology.

Congenital hypogonadotropic hypogonadism during childhood: presentation and genetic analyses in 46 boys.

BACKGROUND: The majority of the patients reported with mutations in isolated hypogonadotropic hypogonadism (HH) are adults. We analysed the presentation and the plasma inhibin B and anti-müllerian hormone (AMH) concentrations during childhood and adolescence, and compared them to the genetic results. METHODS: This was a retrospective, single-center study of 46 boys with HH. RESULTS: Fourteen (30.4%) had Kallmann syndrome (KS), 4 (8.7%) had CHARGE syndrome and 28 (60.9%) had HH without olfaction deficit nor olfactive bulb hypoplasia. Eighteen (39%) had an associated malformation or syndromes. At diagnosis, 22 (47.8%) boys were aged

Mutation analysis of NR5A1 encoding steroidogenic factor 1 in 77 patients with 46, XY disorders of sex development (DSD) including hypospadias.

BACKGROUND: Mutations of the NR5A1 gene encoding steroidogenic factor-1 have been reported in association with a wide spectrum of 46,XY DSD (Disorder of Sex Development) phenotypes including severe forms of hypospadias. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the frequency of NR5A1 gene mutations in a large series of patients presenting with 46,XY DSD and hypospadias. Based on their clinical presentation 77 patients were classified either as complete or partial gonadal dysgenesis (uterus seen at genitography and/or surgery, n = 11), ambiguous external genitalia without uterus (n = 33) or hypospadias (n = 33). We identified heterozygous NR5A1 mutations in 4 cases of ambiguous external genitalia without uterus (12.1%; p.Trp279Arg, pArg39Pro, c.390delG, c140_141insCACG) and a de novo missense mutation in one case with distal hypospadias (3%; p.Arg313Cys). Mutant proteins showed reduced transactivation activity and mutants p.Arg39Pro and p.Arg313Cys did not synergize with the GATA4 cofactor to stimulate reporter gene activity, although they retained their ability to physically interact with the GATA4 protein. CONCLUSIONS/SIGNIFICANCE: Mutations in NR5A1 were observed in 5/77 (6.5%) cases of 46,XY DSD including hypospadias. Excluding the cases of 46,XY gonadal dysgenesis the incidence of NR5A1 mutations was 5/66 (7.6%). An individual with isolated distal hypopadias carried a de novo heterozygous missense mutation, thus extending the range of phenotypes associated with NR5A1 mutations and suggesting that this group of patients should be screened for NR5A1 mutations.

Clinical, biological and genetic analysis of prepubertal isolated ovarian cyst in 11 girls.

BACKGROUND: The cause of isolated gonadotropin-independent precocious puberty (PP) with an ovarian cyst is unknown in the majority of cases. Here, we describe 11 new cases of peripheral PP and, based on phenotypes observed in mouse models, we tested the hypothesis that mutations in the GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX may be associated with this phenotype. METHODOLOGY/PRINCIPAL FINDINGS: 11 girls with gonadotropin-independent PP were included in this study. Three girls were seen for a history of prenatal ovarian cyst, 6 girls for breast development, and 2 girls for vaginal bleeding. With one exception, all girls were seen before 8 years of age. In 8 cases, an ovarian cyst was detected, and in one case, suspected. One other case has polycystic ovaries, and the remaining case was referred for vaginal bleeding. Four patients had a familial history of ovarian anomalies and/or infertility. Mutations in the coding sequences of the candidate genes GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX were not observed. CONCLUSIONS/SIGNIFICANCE: Ovarian PP shows markedly different clinical features from central PP. Our data suggest that mutations in the GNAS1, NR5A1, LHCGR, FSHR StAR, DMRT4 and NOBOX genes are not responsible for ovarian PP. Further research, including the identification of familial cases, is needed to understand the etiology of ovarian PP.

Lack of association between genetic polymorphisms in enzymes associated with folate metabolism and unexplained reduced sperm counts.

BACKGROUND: The metabolic pathway of folate is thought to influence DNA stability either by inducing single/double stranded breaks or by producing low levels of S-adenosyl-methionine leading to abnormal gene expression and chromosome segregation. Polymorphisms in the genes encoding enzymes in the folate metabolism pathway show distinct geographic and/or ethnic variations and in some cases have been linked to disease. Notably, the gene Methylenetetrahydrofolate reductase (MTHFR) in which the homozygous (TT) state of the polymorphism c.665C>T (p.A222V) is associated with reduced specific activity and increased thermolability of the enzyme causing mild hyperhomocysteinemia. Recently several studies have suggested that men carrying this polymorphism may be at increased risk to develop infertility. METHODOLOGY/PRINCIPAL FINDINGS: We have tested this hypothesis in a case/control study of ethnic French individuals. We examined the incidence of polymorphisms in the genes MTHFR (R68Q, A222V and E429A), Methionine synthase reductase MTRR; (I22M and S175L) and Cystathionine beta-synthase (CBS; G307S). The case population consisted of DNA samples from men with unexplained azoospermia (n = 70) or oligozoospermia (n = 182) and the control population consisted of normospermic and fertile men (n = 114). We found no evidence of an association between the incidence of any of these variants and reduced sperm counts. In addition haplotype analysis did not reveal differences between the case and control populations. CONCLUSIONS/SIGNIFICANCE: We could find no evidence for an association between reduced sperm counts and polymorphisms in enzymes involved in folate metabolism in the French population.

Mutational analysis of the WNT gene family in women with Mayer-Rokitansky-Kuster-Hauser syndrome.

The aim of this study is to determine if Müllerian agenesis has a genetic basis linked to the WNT genes. Genomic DNA analyses for mutations in the coding sequences of four members of this family in a series of 11 women with Mayer-Rokitansky-Kuster-Hauser syndrome found four variants in the coding sequence of these genes, but causal mutations were not observed. This supports the hypothesis that mutations in the coding sequence of WNT4, WNT5A, WNT7A, and WNT9B are not responsible for the Mayer-Rokitansky-Kuster-Hauser syndrome.