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International audience; R-spondin proteins are secreted agonists of canonical WNT/β-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.

Introduction: Next Generation Sequencing is revolutionising our understanding of variation in the human genome and as costs reduce the sequencing of patient’s genomes is become more routine.Areas covered: Here, we review the current challenges in the field and some of the efforts that are underway to resolve them. We describe how these technologies are impacting on our understanding of human sex development and the profound clinical implications of these technologies on conditions such as Disorders of Sex Development (DSD).Expert commentary: The sheer wealth of genomic data is generating new challenges—some are technical such as variant calling, or predicting the functional consequence of a variant—whereas others are more profound, such as establishing the link between extensive genomic information and the clinical presentation. Predicting disease phenotypes from genetic sequences is often extremely difficult because the genotype-phenotype relationship has proven to be far more complex than antici...

SOX8 is an HMG-box transcription factor closely related to SRY and SOX9. Deletion of the gene encoding Sox8 in mice causes reproductive dysfunction but the role of SOX8 in humans is unknown. Here, we show that SOX8 is expressed in the somatic cells of the early developing gonad in the human and influences human sex determination. We identified two individuals with 46, XY disorders/differences in sex development (DSD) and chromosomal rearrangements encompassing the SOX8 locus and a third individual with 46, XY DSD and a missense mutation in the HMG-box of SOX8. In vitro functional assays indicate that this mutation alters the biological activity of the protein. As an emerging body of evidence suggests that DSDs and infertility can have common etiologies, we also analysed SOX8 in a cohort of infertile men (n=274) and two independent cohorts of women with primary ovarian insufficiency (POI; n=153 and n=104). SOX8 mutations were found at increased frequency in oligozoospermic men (3.5%; P < 0.05) and POI (5.06%; P=4.5×10-5) as compared with fertile/normospermic control populations (0.74%). The mutant proteins identified altered SOX8 biological activity as compared with the wild-type protein. These data demonstrate that SOX8 plays an important role in human reproduction and SOX8 mutations contribute to a spectrum of phenotypes including 46, XY DSD, male infertility and 46, XX POI. Fil: Portnoi, Marie France. Inserm; Francia. Sorbonne Université. Faculté de Medecine; Francia. Hôpital Armand Trousseau; Francia Fil: Dumargne, Marie Charlotte. Instituto Pasteur; Francia Fil: Rojo, Sandra. Instituto Pasteur; Francia Fil: Witchel, Selma F.. University of Pittsburgh; Estados Unidos Fil: Duncan, Andrew J.. Great Ormond Street Hospital for Children; Reino Unido Fil: Eozenou, Caroline. Instituto Pasteur; Francia Fil: Bignon Topalovic, Joelle. Instituto Pasteur; Francia Fil: Yatsenko, Svetlana A.. University of Pittsburgh; Estados Unidos Fil: Rajkovic, Aleksandar. University of Pittsburgh; Estados Unidos Fil: Reyes Mugica, Miguel. University of Pittsburgh; Estados Unidos Fil: Almstrup, Kristian. Rigshospitalet; Dinamarca Fil: Fusee, Leila. Instituto Pasteur; Francia Fil: Srivastava, Yogesh. Chinese Academy of Sciences; República de China Fil: Chantot Bastaraud, Sandra. Hôpital Armand Trousseau; Francia Fil: Hyon, Capucine. Hôpital Armand Trousseau; Francia. Inserm; Francia Fil: Louis Sylvestre, Christine. Institut Mutualiste Montsouris; Francia Fil: Validire, Pierre. Institut Mutualiste Montsouris; Francia Fil: de Malleray Pichard, Caroline. Hôpital Cochin; Francia Fil: Ravel, Celia. Centre Hospitalier Universitaire de Rennes; Francia Fil: Christin Maitre, Sophie. Inserm; Francia. Hôpital Saint-Antoine; Francia Fil: Brauner, Raja. Universite de Paris; Francia Fil: Rossetti, Raffaella. Università degli Studi di Milano; Italia. Istituto Auxologico Italiano; Italia Fil: Persani, Luca. Istituto Auxologico Italiano; Italia. Università degli Studi di Milano; Italia Fil: Charreau, Eduardo Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina Fil: Dain, Liliana Beatriz. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina Fil: Chiauzzi, Violeta Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina Fil: Mazen, Inas. National Research Centre ; Egipto Fil: Rouba, Hassan. Institut Pasteur du Maroc; Marruecos Fil: Schluth Bolard, Caroline. Hôpital Femme Mère Enfant; Francia Fil: Mac Gowan, Stuart. University of Dundee; Reino Unido Fil: Mc Lean, W. H. Irwin. University of Dundee; Reino Unido Fil: Patin, Etienne. Instituto Pasteur; Francia Fil: Rajpert De Meyts, Ewa. Rigshospitalet; Dinamarca Fil: Jauch, Ralf. Chinese Academy of Sciences; República de China Fil: Achermann, John C.. Great Ormond Street Hospital for Children; Reino Unido Fil: Siffroi, Jean Pierre. Hôpital Armand Trousseau; Francia Fil: Mc Elreavey, Ken. Instituto Pasteur; Francia Fil: Bashamboo, Anu. Inserm; Francia. Instituto Pasteur; Francia

International audience; Emerging evidence from murine studies suggests that mammalian sex determination is the outcome of an imbalance between mutually antagonistic male and female regulatory networks that canalize development down one pathway while actively repressing the other. However, in contrast to testis formation, the gene regulatory pathways governing mammalian ovary development have remained elusive. We performed exome or Sanger sequencing on 79 46,XX SRY-negative individuals with either unexplained virilization or with testicular/ovotesticular disorders/differences of sex development (TDSD/OTDSD). We identified heterozygous frameshift mutations in NR2F2, encoding COUP-TF2, in three children. One carried a c.103_109delGGCGCCC (p.Gly35Argfs∗75) mutation, while two others carried a c.97_103delCCGCCCG (p.Pro33Alafs∗77) mutation. In two of three children the mutation was de novo. All three children presented with congenital heart disease (CHD), one child with congenital diaphragmatic hernia (CDH), and two children with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). The three children had androgen production, virilization of external genitalia, and biochemical or histological evidence of testicular tissue. We demonstrate a highly significant association between the NR2F2 loss-of-function mutations and this syndromic form of DSD (p = 2.44 × 10-8). We show that COUP-TF2 is highly abundant in a FOXL2-negative stromal cell population of the fetal human ovary. In contrast to the mouse, these data establish COUP-TF2 as a human "pro-ovary" and "anti-testis" sex-determining factor in female gonads. Furthermore, the data presented here provide additional evidence of the emerging importance of nuclear receptors in establishing human ovarian identity and indicate that nuclear receptors may have divergent functions in mouse and human biology.

Congenital heart diseases (CHDs) are the most common cause of all birth defects and account for nearly 25% of all major congenital anomalies leading to mortality in the first year of life. Extracardiac anomalies including urogenital aberrations are present in ∼30% of all cases. Here, we present a rare case of a 46,XY patient with CHD associated with ambiguous genitalia consisting of a clitoris-like phallus and a bifid scrotum. Exome sequencing revealed novel homozygous mutations in the FGFR1 and STARD3 genes that may be associated with the phenotype.

The phenotypic spectrum of patients carrying NR5A1 mutations ranges from 46,XY gonadal dysgenesis to male infertility. Phenotypic variability could be due to digenic or oligogenic inheritance of pathogenic variants in other testis-determining genes. Here, exome sequencing identified 2 pathogenic de novo NR5A1 mutations in 2 patients with 46,XY gonadal dysgenesis, p.Q206Tfs*20 and p.Arg313Cys. The latter patient also carried a missense mutation in MAP3K1. Our data extend the number of NR5A1 gene mutations associated with gonadal dysgenesis. The combination of an NR5A1 mutation with a MAP3K1 variant may explain the phenotypic variability associated with NR5A1 mutations.

Sperm DNA methylation abnormalities have been detected in oligozoospermic men. However, the association between sperm DNA methylation defects, sperm parameters and sperm DNA, and chromatin integrity remains poorly understood. This study was designed to clarify this issue. We recruited a cohort of 92 men (62 normozoospermic and 30 oligoasthenozoospermic) presenting for infertility evaluation during a 1-year period. Sperm global DNA methylation was evaluated by an ELISA-like method, DNA fragmentation was evaluated by flow cytometry-based terminal transferase dUTP nick end-labeling (TUNEL) assay (reported as DNA fragmentation index or DFI), and sperm denaturation was evaluated by aniline blue staining (reported as sperm denaturation index or SDI, a marker of chromatin compaction). We found a significant positive association between sperm global DNA methylation level and conventional sperm parameters (sperm concentration and motility), supported by the results of methylation analysis on H19-DMR. We also identified significant inverse relationships between sperm global DNA methylation, and, both DFI and SDI. However, sperm global DNA methylation level was not related to sperm vitality or morphology. Our findings suggest that global sperm DNA methylation levels are related to conventional sperm parameters, as well as, sperm chromatin and DNA integrity.

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.

International audience

Objective To evaluate the carrier frequency of the pathogenic c.144delC mutation in AURKC gene and the contribution of this mutation in male infertility in a Moroccan population. Design Sanger sequencing of exon 3 in AURKC gene in infertile and control patients in Morocco. Setting Research institute. Patient(s) A total of 326 idiopathic infertile patients, and 450 age-related men. Intervention(s) The incidence of AURKC c.144delC mutation was determined in men with unexplained spermatogenic failure and a control cohort of normospermic fertile men. Main Outcome Measure(s) Genomic DNA was extracted from peripheral blood lymphocytes and the screening of the c.144delC mutation in AURKC gene performed by polymerase chain reaction and sequencing. Result(s) The c.144delC mutation in AURKC gene was found in patients at homozygous and heterozygous states, with an allelic frequency of 2.14%, whereas in controls this mutation was found only in the heterozygous state, with lower frequency (1%). Homozygous patients were characterized by macrocephalic and multiflagellar spermatozoa. Conclusion(s) Our data indicate that the AURKC c.144delC mutation has a relatively high carrier frequency in the Moroccan population; thus, we recommend screening for this deletion in infertile men with a high percentage of large-headed and multiflagellar spermatozoa.

International audience; Located at the cross-road between Europe and Africa, Tunisia is a North African country of 11 million inhabitants. Throughout its history, it has been invaded by different ethnic groups. These historical events, and consanguinity, have impacted on the spectrum and frequency of genetic diseases in Tunisia. Investigations of Tunisian families have significantly contributed to elucidation of the genetic bases of rare disorders, providing an invaluable resource of cases due to particular familial structures (large family size, consanguinity and share of common ancestors). In the present study, we report on and review different aspects of consanguinity in the Tunisian population as a case study, representing several features common to neighboring or historically related countries in North Africa and the Middle East. Despite the educational, demographic and behavioral changes that have taken place during the last four decades, familial and geographical endogamy still exist at high frequencies, especially in rural areas. The health implications of consanguinity in Tunisian families include an increased risk of the expression of autosomal recessive diseases and particular phenotypic expressions. With new sequencing technologies, the investigation of consanguineous populations provides a unique opportunity to better evaluate the impact of consanguinity on the genome dynamic and on health, in addition to a better understanding of the genetic bases of diseases. © 2014 S. Karger AG, Basel.

Disorders of sex development (DSD) are defined as 'congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical' [Lee et al., Pediatrics 2006;118:e488-e500]. Studies conducted in Western countries, with low rates of consanguinity, show that truly ambiguous genitalia have an estimated incidence of 1:5,000 births. There are indications that the prevalence of DSD is higher in endogamous communities. The incidence of ambiguous genitalia in Saudi Arabia has been estimated at 1:2,500 live births; whilst in Egypt, it has been estimated at 1:3,000 live births. This may be due in part to an increase in disorders of androgen synthesis associated with 46,XX DSD. There is clearly a need for further studies to address the frequency of DSD in communities with high levels of consanguinity. This will be challenging, as an accurate diagnosis is difficult and expensive even in specialized centres. In developing countries with high levels of consanguinity, these limitations can be compounded by cultural, social and religious factors. Overall there is an indication that consanguinity may lead to an increase in incidences of both 46,XY and 46,XX DSD, and a co-ordinated study of populations with higher incidences of consanguinity/endogamy is needed to resolve this.

The objective of this study was to identify disease-causing mutations in a Sri Lankan male child presenting with ambiguous genitalia and psychomotor delay using the exome sequencing approach. A novel mutation in the aristaless-related homeobox (ARX) gene causing a hemizygous nucleotide substitution in exon 5 was identified (NM_139058.2 (ARX): c.1614G>T; p.K538N). This change causes a nonsynonymous substitution in the aristaless domain within the ARX protein which is predicted to be deleterious. This is the first reported case of ambiguous genitalia and psychomotor delay associated with this novel missense mutation within the ARX protein, and it highlights the value of exome sequencing even in sporadic cases.

Temozolomide is an oral alkylating agent with proven efficacy in recurrent high-grade glioma. The antitumour activity of this molecule is attributed to the inhibition of replication through DNA methylation. However, this methylation may also perturb other DNA-dependent processes, such as spermatogenesis. The ability to father a child may be affected by having this treatment. Here we report a pregnancy and a baby born after 6 cures of temozolomide.The quality of gametes of the father has been studied through these cures and after the cessation of treatment. Sperm parameters, chromosomal content and epigenetic profiles of H19, MEST and MGMT have been analysed.Sperm counts decrease significantly and hypomethylation of the H19 locus increase with time even staying in the normal range.This is the first report of an epigenetic modification in sperm after temozolomide treatment suggesting a potential risk for the offspring. A sperm cryopreservation before the initiation of temozolomide treatment should be recommended.

cited By 0; International audience; In this study, we carried out whole exome sequencing (WES) analysis in one Libyan patient in order to identify the molecular aetiology of hereditary epidermolysis bullosa (HEB).

International audience; 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.

The human Y chromosome is essential for human sex determination and spermatogenesis. The long arm contains the azoospermia factor (AZF) region. Microdeletions in this region are responsible for male infertility. The objective of this study was to determine the frequency of Y microdeletions in Algerian infertile males with azoospermia and oligoasthenoteratozoospermia syndrome (OATS) and to compare the prevalence of these abnormalities with other countries and regions worldwide. A sample of 80 Algerian infertile males with a low sperm count (1-20 × 106 sperms/ml) as well as 20 fertile male controls was screened for Y chromosome microdeletions. 49 men were azoospermic and 31 men had OATS. Genomic DNA was isolated from blood and polymerase chain reaction was carried out with a set of 6 AZFa, AZFb and AZFc STS markers to detect the microdeletions as recommended by the European Academy of Andrology. Among the 80 infertile men screened for microdeletion, 1 subject was found to have microdeletions in the AZFc (sY254 and sY255) region. The deletion was found in azoospermic subjects (1/49, 2%). The overall AZF deletion frequency was low (1/80, 1.3%). AZF microdeletions were observed neither in the OATS group nor in the control group. The frequency of AZF microdeletions in infertile men from Algeria was comparable to those reported in the literature. We suggest analyzing 6 STS in the first step to detect Y microdeletions in our population.

Cell lineages of the early human gonad commit to one of the two mutually antagonistic organogenetic fates, the testis or the ovary. Some individuals with a 46,XX karyotype develop testes or ovotestes (testicular or ovotesticular disorder of sex development; TDSD/OTDSD), due to the presence of the testis-determining gene, SRY. Other rare complex syndromic forms of TDSD/OTDSD are associated with mutations in pro-ovarian genes that repress testis development (e.g. WNT4); however, the genetic cause of the more common non-syndromic forms is unknown. Steroidogenic factor-1 (known as NR5A1) is a key regulator of reproductive development and function. Loss-of-function changes in NR5A1 in 46,XY individuals are associated with a spectrum of phenotypes in humans ranging from a lack of testis formation to male infertility. Mutations in NR5A1 in 46,XX women are associated with primary ovarian insufficiency, which includes a lack of ovary formation, primary and secondary amenorrhoea as well as early menopause. Here, we show that a specific recurrent heterozygous missense mutation (p.Arg92Trp) in the accessory DNA-binding region of NR5A1 is associated with variable degree of testis development in 46,XX children and adults from four unrelated families. Remarkably, in one family a sibling raised as a girl and carrying this NR5A1 mutation was found to have a 46,XY karyotype with partial testicular dysgenesis. These unique findings highlight how a specific variant in a developmental transcription factor can switch organ fate from the ovary to testis in mammals and represents the first missense mutation causing isolated, non-syndromic 46,XX testicular/ovotesticular DSD in humans.

In this review we will consider the gene mutations responsible for the non-syndromic forms of disorders of sex development (DSD) and how recent genetic findings are providing insights into the mechanism of sex determination. High-throughput sequencing technologies are having a major impact on our understanding of the genetic basis of rare human disorders, including DSD. The study of human DSD is progressively revealing subtle differences in the genetics of the sex-determining system between the mouse and the human. This plasticity of the sex-determining pathway is apparent in (a) the difference in phenotypes in human and mouse associated with the same gene, (b) the different gene regulatory mechanisms between human and mouse, and finally (c) the different and unexpected reproductive phenotypes seen in association with mutations in well-studied sex-determining genes.

Background Skin cancers (SC) are complex diseases that develop from complex combinations of genetic and environmental risk factors. One of the most severe and rare genetic diseases predisposing to SC is the Xeroderma pigmentosum (XP) syndrome. Objectives First, to identify the genetic etiology of XP and to better classify affected patients. Second, to provide early molecular diagnosis for pre-symptomatic patient and finally to offer genetic counseling for related individuals. Methods Whole Exome Sequencing (WES) and Run Of Homozygosity (ROH) were performed for two patients belonging to two different multiplex consanguineous families. The identified mutations were confirmed by Sanger sequencing and researched in ten Tunisian families including a total of 25 affected individuals previously suspected as having XP group V (XP-V) form. All patients had mild dermatological manifestations, absence of neurological abnormalities and late onset of skin tumors. Results Screening for functional variations showed the presence of the ERCC2 p.Arg683Gln in XP14KA-2 patient and a novel mutation, DDB2 p. (Lys381Argfs*2), in XP51-MAH-1 patient. Sanger sequencing and familial segregation showed that the ERCC2 mutation is present at a homozygous state in 10 affected patients belonging to 3 families. The second mutation in DDB2, is present at a homozygous state in 5 affected cases belonging to the same family. These two mutations are absent in the remaining 10 affected patients. The ERCC2 c.2048G > A mutation is present in a medium ROH region (class B) suggesting that it mostly arises from ancient relatedness within individuals. However, the c.1138delG DDB2 mutation is present in a large ROH region (class C) suggesting that it arises from recent relatedness. Conclusion To our knowledge, this is the first study that identifies XP-D and XP-E complementation groups in Tunisia. These two groups are very rare and under-diagnosed in the world and were not reported in North Africa.

Background The mechanism that initiates the onset of puberty is largely unknown but the age of onset is mainly under genetic control and influenced by environmental factors including nutrition. The coexistence in the same family of central precocious puberty and advanced puberty, both representing early puberty, suggests that they may represent a clinical spectrum of the same trait due to early activation of the GnRH pulse generator. We therefore evaluated the mode of inheritance of early puberty in a large series of familial cases. Methods A retrospective, single center study was carried out on 154 probands (116 girls and 38 boys), from 139 families seen for idiopathic central precocious puberty (onset before 8 years in girls and 9–10 years in boys, n = 93) and/or advanced puberty (onset between 8 and 10 years in girls and 10 and 11 years in boys, n = 61) seen over a period of 8 years. Results Of the 139 families, 111 (80.4 %) had at least one affected 1st degree relatives, 17 (12 %) had only 2nd, 5 (3.6 %) only 3rd and 3 (2.2 %) had both 2nd and 3rd degree affected individuals. In the two remaining families, the unaffected mother had affected girls from two unaffected fathers. In the majority of families the inheritance of the phenotype was consistent with autosomal dominant mode of transmission with incomplete penetrance. An exclusively maternal mode of transmission could be observed or inferred in 83 families, paternal in only 2 families (p

The phenotypic spectrum of patients carrying NR5A1 mutations ranges from 46,XY gonadal dysgenesis to male infertility. Phenotypic variability could be due to digenic or oligogenic inheritance of pathogenic variants in other testis-determining genes. Here, exome sequencing identified 2 pathogenic de novo NR5A1 mutations in 2 patients with 46,XY gonadal dysgenesis, p.Q206Tfs*20 and p.Arg313Cys. The latter patient also carried a missense mutation in MAP3K1. Our data extend the number of NR5A1 gene mutations associated with gonadal dysgenesis. The combination of an NR5A1 mutation with a MAP3K1 variant may explain the phenotypic variability associated with NR5A1 mutations.

Background The mechanism that initiates the onset of puberty is largely unknown but the age of onset is mainly under genetic control and influenced by environmental factors including nutrition. Familial forms of constitutional delay of puberty (CDP) suggest the involvement of genetic factors. The purpose of this study is to describe the presentation and the mode of inheritance of CDP in a series of familial cases. Methods A retrospective, single center study was carried out over 10 years on 48 probands (14 girls and 34 boys) from 48 families seen for CDP with a familial component. Results Of the 48 probands, 46 (96 %) had at least one affected 1st degree relatives and 2 (4 %, 2 boys) had only 2nd degree relatives affected. In girls, 11 families (79 %) exhibited exclusive maternal inheritance, 1 (7 %) paternal inheritance and 2 (14 %) both maternal and paternal inheritance. In boys, 14 families (41 %) exhibited exclusive maternal inheritance, 12 (35 %) paternal inheritance and 8 (24 %) both maternal and paternal inheritance. In the boys with bilineal inheritance, the ages at onset of puberty (16 ± 1.41 years) and at evaluation (16.05 ± 2.47 years) were higher than in those with unilineal inheritance (15.25 ± 0.35 and 15.1 ± 0.42 years respectively), but the difference was not significant. Conclusions In girls exclusive maternal inheritance seems to be the major mode of inheritance whereas for boys the mode of inheritance was almost equally maternal, paternal or bilineal. Clinical phenotype of boys with bilineal inheritance seems to be more severe, but the difference did not reach statistical significance, perhaps because of the small sample size. This greater severity of the phenotype in boys with bilineal inheritance is likely due to inheriting different puberty timing genes from each parent. Future research should be directed at identifying such genes.

Mullerian agenesis, also termed the Mayer–Rokitansky–Kuster–Hauser syndrome (MRKHS) is a disorder with an incidence of approximately 1 in 4500 newborn girls. This study screened 12 patients with MRKHS for mutations in two genes, LAMC1 and DLGH1 , involved in the development of Mullerian structures and found 10 previously described variants and no novel variants in the coding sequence. It is highly unlikely that these variants are pathological since these are common in the general population. It is the first time that an extensive study of LAMC1 and DLGH1 has been undertaken in patients with MRKHS. The data support the notion that mutations in the coding sequence of LAMC1 and DLGH1 may not be associated with MRKHS.

Primary ovarian insufficiency (POI) is defined as cessation of menstruation with associated elevation of gonadotropin levels as a result of decreased ovarian function before the age of 40. The incidence of POI is 1% in women prior to age 40, and 0.1% prior to age 30. There is evidence of a strong genetic component associated with POI. However, the gene mutations/variations influencing POI still remain uncharacterized. NR5A1, a member of the nuclear receptor superfamily, is a key transcriptional regulator of genes involved in the hypothalamic-pituitary-gonadal steroidogenic axis. Newborn mice deficient in NR5A1 lack both gonads and adrenal glands and have impaired expression of pituitary gonadotrophins. NR5A1 is also expressed in multiple cell types in the fetal, postnatal, prepubertal and mature ovary. Until 2008, 18 NR5A1 mutations were described in the human. Three of these were identified in individuals with adrenal insufficiency, two associated with 46,XY disorders of sex development (DSD) and the third a 46,XX female with conserved ovarian function. Other mutations were associated with various anomalies of testis development with no evidence of adrenal failure. We have identified further 19 mutations in NR5A1 including mutations in four familial cases having individuals with 46,XY DSD as well as POI. A further analysis of 25 sporadic cases of POI revealed two additional mutations. Functional analysis revealed that each mutant protein had altered transactivational properties on gonadal promoters. These data reveal novels insights into the role of NR5A1 in ovarian developmental and function and indicate that mutations of the NR5A1 gene may be a significant cause of human ovarian insufficiency.

We screened 100 individuals with anomalies of testicular development or function for mutations in the TSPYL1 gene. A 46,XY female with complete gonadal dysgenesis carried a p.K320R mutation in the highly conserved NAP domain, and a 46,XY male with idiopathic azoospermia harbored a p.R89H mutation, and this data supports the hypothesis that mutations in TSPYL1 may contribute to anomalies of testicular development/function.

L’insuffisance ovarienne primaire (IOP) se caracterise par un arret de la fonction ovarienne normale avant l’âge de 40 ans. Elle touche environ 1 % des femmes avec souvent une transmission familiale evoquant une contribution genetique. NR5A1 est un recepteur nucleaire regulant la transcription de nombreux genes impliques dans le developpement sexuel et la reproduction. Plusieurs mutations dans le gene correspondant ont ete associees a des anomalies du developpement des surrenales ou des testicules. Nous avons identifie des mutations dans NR5A1 associees a une IOP incluant des cas 46,XX et 46,XY dans une meme famille. Ce gene joue donc un role important dans le developpement et le fonctionnement de l’ovaire. Cependant, plusieurs questions importantes demeurent. Quelle est la prevalence des mutations dans NR5A1 chez des patientes presentant diverses formes d’insuffisance ovarienne ? Quelles sont les correlations entre genotype et phenotype ? Y a-t-il une perte progressive de la fonction ovarienne chez les individus porteurs de mutations dans NR5A1 ? La reponse a ces questions permettra une meilleure comprehension du fonctionnement ovarien conduisant a l’elaboration de nouveaux outils diagnostiques et therapeutiques.

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.

Primary ovarian insufficiency, also known as premature ovarian failure, is characterized by loss of function of the ovaries before the age 40. Observational evidence of familial associations suggests a genetic basis for ovarian insufficiency. Despite extensive research, specific genetic causes have not been identified. A nuclear receptor, NR5A1, also called Ad4 binding protein or steroidogenic factor 1, is a protein that regulates the transcription of genes involved in the hypothalamic―pituitary―steroidogenic axis that play a key role in sexual development and reproduction. NR5A1 I is expressed in multiple ovarian cell types during fetal development, postnatal and prepubertal growth, and at maturity. In this study, the investigators tested the hypothesis that mutations in NR5A1 are associated with disorders of ovarian development and function. NR5A1 was sequenced in affected study subjects who were members of 4 families with a history of 46,XY disorders of sex development and 46,XX ovarian insufficiency and 25 women with 46,XX sporadic ovarian insufficiency. A panel of 1465 subjects of various ancestral origins who did not carry NRSA1 mutations served as controls. There was no clinical evidence of adrenal insufficiency among any of the affected patients. Mutations in the NR5A1 gene were found among members of each of the 4 families and 2 of the 25 subjects with isolated ovarian insufficiency. Analysis of the NRSA1 gene revealed a series of in-frame, frame-shift and missense mutations. Testing the effect of each of the NRSA1 mutations on protein function revealed a severe quantitative impairment of NRSA1 transactivational activity. A range of ovarian anomalies, including 46,XY gonadal dysgenesis and 46,XX primary ovarian insufficiency, were associated with the mutations. None of these mutations were found in any of the unaffected control subjects. These findings indicate that mutations in NRSA1 are associated with a number of ovarian anomalies characterized by loss of ovarian reproductive capacity.

BACKGROUND: Deletions in the azoospermia factor (AZF) region of the Y chromosome are frequent in infertile men. The clinical consequences and the mode of inheritance of these deletions are not yet clear. METHODS: Y chromosome deletion mapping and quantitative PCR analysis of the DAZ-gene copy number, supplemented with haplogroup typing in deleted patients, were performed, in combination with clinical assessments in 264 fathers and their sons conceived by assisted reproduction techniques (ART), and in 168 fertile men with normal sperm concentration. RESULTS: In the ART fathers group, a complete AZFc deletion was detected in 0.4% (1/264). AZFc rearrangements/polymorphisms were found in 6.8% (18/264; 95% CI: 4.4-10.5), which was significantly more frequent (P = 0.021) than in the controls (3/168; 1.8%, 95% CI: 0.6-5.1). All deletions were transmitted to the sons, without any clinical symptoms in early childhood. In the fathers, there was no significant correlation between the DAZ copy number and the severity of spermatogenic failure. CONCLUSIONS: AZFc rearrangements/polymorphisms are transmitted to sons and may represent a risk factor for decreased testis function and male subfertility, which needs confirmation in further studies in larger cohorts. However, deletions of two DAZ gene copies are compatible with normal spermatogenesis and fertility.

Le chromosome Y humain contient de nombreux genes et familles de genes necessaires a la spermatogenese. La majeure partie de ces genes est localisee au sein de sequences repetees frequemment soumises a des rearrangements. Les deletions des regions AZFa, AZFb et AZFc sont retrouvees chez 10 a 15 % des hommes presentant une oligozoospermie severe ou une azoospermie. Plusieurs deletions partielles de la region AZFc ont ete decrites. L'une d'entre elles emporte la moitie des genes de la region AZFc. Ses consequences sur la fertilite dans la population eurasienne semblent nulles ou minimes. Une autre deletion partielle denommee gr/gr emporte plusieurs genes de la region AZFc et a ete proposee comme un facteur de risque d'infertilite. Neanmoins, cette relation causale n'est pas evidente car il existe en fait plusieurs varietes de deletions gr/gr et leur repartition varie considerablement en fonction des origines ethniques et geographiques. Ces deletions semblent fixees sur certaines lignees de chromosome Y et n'auraient que peu ou pas d'influence sur la fertilite. La majorite des donnees concernant l'organisation chromosomique et le contenu genique du chromosome Y a ete deduite de la sequence de reference du chromosome Y deposee dans la base de donnees du NCBI. L'etablissement de donnees sur ce type de rearrangement dans la population generale n'a ete que recemment mis en œuvre. Ces etudes recentes ont souligne l'extreme diversite des polymorphismes de structure du chromosome Y dans la population generale. Correler ces polymorphismes de structure a la variabilite phenotypique sera l'enjeu de futures etudes. Il est vraisemblable que ces etudes aboutiront a la caracterisation non plus d'une sequence de reference unique du chromosome Y mais de plusieurs sequences de reference.

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.

Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common congenital facial defects, with an incidence of 1 in 700–1,000 live births among individuals of European descent. Several linkage and association studies of NSCL/P have suggested numerous candidate genes and genomic regions. A genomewide linkage analysis of a large multigenerational family (UR410) with NSCL/P was performed using a single-nucleotide–polymorphism array. Nonparametric linkage (NPL) analysis provided significant evidence of linkage for marker rs728683 on chromosome 18q21.1 (NPL=43.33 and P=.000061; nonparametric LOD=3.97 and P=.00001). Parametric linkage analysis with a dominant mode of inheritance and reduced penetrance resulted in a maximum LOD score of 3.61 at position 47.4 Mb on chromosome 18q21.1. Haplotype analysis with informative crossovers defined a 5.7-Mb genomic region spanned by proximal marker rs1824683 (42,403,918 bp) and distal marker rs768206 (48,132,862 bp). Thus, a novel genomic region on 18q21.1 was identified that most likely harbors a high-risk variant for NSCL/P in this family; we propose to name this locus “OFC11” (orofacial cleft 11).

In elongating spermatids, human sperm chromatin undergoes a complex compaction in which the transition proteins are extensively replaced by the protamine proteins. Several human studies demonstrate that expression of the protamine proteins is altered in some men with male infertility. For this study, we screened the PRM1 (protamine 1) gene for mutations in a large cohort of 281 men seeking infertility treatment. We identified the c.102G>T transversion that results in an p.Arg34Ser amino acid change in two men. One of these patients presented with oligozoospermia associated with increased sperm DNA fragmentation. The second individual was normospermic but together with his partner sought treatment for idiopathic couple infertility. We also identified a novel missense mutation (c.119G>A, p.Cys40Tyr) in a man with oligoasthenozoospermia. These mutations were not observed in control populations. Interestingly, we also detected variants both 5' and 3' to the PRM1 open-reading frame specifically in infertile individuals. Four individuals with unexplained severe oligozoospermia were heterozygote for a c.-107G>C change that is located at -15 bp from the transcription initiation site of the gene. This mutation may influence PRM1 expression. In addition, a c.*51G>C variant was detected in the 3'UTR of PRM1 specifically in a man with severe oligoasthenozoospermia.

Cryptorchidism affects 1% to 9% of full-term male neonates. Hypospadias is the second most frequent congenital anomaly seen in newborn males. These pathological conditions are part of the testicular dysgenesis syndrome. Insulin-like factor 3 and LGR8 (leucine-rich repeat-containing G protein-coupled receptor 8), acting as a hormone and a receptor, respectively, are involved in control of the first phase of testicular descent via gubernacular development.The study group consisted of 184 patients, of whom 52 presented with unilateral cryptorchidism, 37 presented with bilateral cryptorchidism, 19 presented with cryptorchidism and hypospadias, 1 presented with bilateral cryptorchidism and micropenis, and 75 presented with isolated hypospadias. A control panel consisted of 270 controls, including 127 fertile, and 143 fertile noncryptorchid males. Insulin-like factor 3 mutations were analyzed by direct sequencing and restriction enzyme digestion. We analyzed the ability of the mutant insulin-like factor 3 peptides identified in this study to activate LGR8 receptor in an ex vivo assays.We identified 3 novel insulin-like factor 3 variants, including C-19G, V18M and R105H, in 3 of the 109 patients (2.75%) but in none of the 270 controls. The V18M mutation in the insulin-like factor 3 signal peptide had a significant deleterious effect in activating LGR8 receptor in ex vivo studies (p0.05). To our knowledge we report the first variant in the promoter region of the insulin-like factor 3 gene in a patient with cryptorchidism in association with micropenis.Mutations involving the insulin-like factor 3 gene may contribute to other anomalies of male genital development, such as micropenis.

The role of a genetically impaired epidermal barrier as a major predisposing factor in the pathogenesis of atopic disorders is currently under closer investigation. Variants on three candidate genes (SPINK5, KLK7 and FLG) have been associated with atopic dermatitis. A functional relevance has already been established for filaggrin variants, but not for SPINK5 and KLK7 polymorphisms. The objectives of this study were to confirm the association between SPINK5, KLK7, FLG variants and atopic dermatitis and to assess how variants influence selected phenotypic traits. This cross-sectional study was carried out over 20 months in 99 children and adults with atopic dermatitis (median age 7 years). The following items were analysed: SCORAD, TEWL, ichthyosis vulgaris, presence of asthma, total IgE serum levels. The SPINK5 E420K SNP, the KLK7 4bp insertion polymorphism and the filaggrin mutants (R510X and 2282del4) were analysed as described previously. The control group for genetic analysis was recruited in an ethnically matched, phenotypically anonymous cohort (n=102). The allelic frequencies were 0.525 for SPINK5, 0.26 for KLK7 polymorphisms, 0.101 and 0.075 for 2282del4 and R501X FLG mutants, respectively. The association of atopic dermatitis with filaggrin variants was confirmed, but not that of SPINK5 or KLK7 polymorphisms. SCORAD and TEWL measurements were not influenced by any of the variants. The SPINK5 polymorphism was associated with high IgE serum levels (p=0.011). Abnormal barrier genes do not influence the severity of atopic dermatitis. The SPINK5 gene polymorphism may modulate systemic immune effects favouring the IgE response to atopens. TEWL does not allow the characterization of subsets of patients with or without abnormal barrier genes.

Pituitary stalk interruption syndrome (PSIS) and holoprosencephaly (HPE) are congenital midline defects. Rare mutations in the sonic hedgehog (SHH) signaling gene CDON have recently been reported in patients with HPE.To report a unique case of PSIS with a maternally inherited nonsense mutation in the SHH signaling protein CDON.We performed exome sequencing on a case of PSIS. Control databases (1000 Genomes, dbSNP, Exome Variant Server, ExAC Browser) and an ancestry-matched control panel were screened upon identification of CDON mutation.We identified a novel heterozygous nonsense mutation (c.2764TC, Glu922Ter) in a case of PSIS without HPE who presented with neonatal hypoglycemia and cholestasis associated with GH, TSH, and ACTH deficiencies. This mutation was absent in all control databases and from 400 healthy ancestry-matched control subjects. The mutation was inherited from the patient's mother, who was operated on in childhood for strabismus. The absence of this variant in control samples suggests that it is likely to be responsible for the phenotype.We report for the first time a mutation in the CDON gene associated with PSIS.

Several new genes and pathways have been identified in recent years associated with human errors of sex-determination or DSD. SOX family gene mutations, as well as mutations involving GATA4, FOG2 and genes involved in MAP kinase signaling have been associated with virilization in 46,XX individuals or with 46,XY gonadal dysgenesis. Furthermore, mutations involving another key gene in sex-determination, NR5A1, are now known to be an important cause spermatogenic failure in the male and ovarian insufficiency in the female. These new findings offer insights into human sex-determination and highlight important differences between the human and mouse model. This review will critically examine the evidence linking gene mutations, especially MAP3K1, to non-syndromic forms of human 46,XY gonadal dysgenesis or XX testicular/ovotesticular.

International audience; Disorders of Sex Development (DSD) are a heterogeneous group of disorders affecting gonad and/or genito-urinary tract development and usually the endocrine-reproductive system. A genetic diagnosis is made in only around 20% of these cases. The genetic causes of 46,XX-SRY negative testicular DSD as well as ovotesticular DSD are poorly defined. Duplications involving a region located ∼600 kb upstream of SOX9, a key gene in testis development, were reported in several cases of 46,XX DSD. Recent studies have narrowed this region down to a 78 kb interval that is duplicated or deleted respectively in 46,XX or 46,XY DSD. We identified three phenotypically normal patients presenting with azoospermia and 46,XX testicular DSD. Two brothers carried a 83.8 kb duplication located ∼600 kb upstream of SOX9 that overlapped with the previously reported rearrangements. This duplication refines the minimal region associated with 46,XX-SRY negative DSD to a 40.7-41.9 kb element located ∼600 kb upstream of SOX9. Predicted enhancer elements and evolutionary-conserved binding sites for proteins known to be involved in testis determination are located within this region.

Molecular anomalies of the Y chromosome leading to male infertility are mainly microdeletions of the long arm of the Y chromosome. Three recurrently deleted portions of the long arm are the AZFa, AZFb and AZFc (AZF: Azoospermia Factor) regions. Complete deletions of the AZFc region are found in 10% of cases of severe male infertility. In addition to the AZF deletions, certain classes of Y chromosome (haplogroups) may also predispose to male infertility and could be transmitted to future male descents by various Assisted Reproductive Techniques (ART). Since the first discovery of microdeletions, the sequence of the Y chromosome has become available, revealing the mechanisms underlying deletion formation and also resulting in a coherent screening strategy. Recently, partial deletions of the AZF regions have been described. The significance of these deletions in the clinical context remains to be defined.

Recently, mutations in the X-linked ubiquitin protease 26 (USP26) gene have been proposed to be associated with male infertility. In particular a 371insACA, 494T>C and 1423C>T haplotype, which results in a T123-124ins, L165S and H475Y amino acid change respectively, has been reported to be associated with Sertoli cell-only syndrome (SCOS) and an absence of sperm in the ejaculate. Here, we demonstrate that two of these changes actually correspond to the ancestral sequence of the gene and that the USP26 haplotype is present in significant frequencies in sub-Saharan African and South and East Asian populations, including in individuals with known fertility. This indicates that the allele is not associated with infertility. The pattern of frequency distribution of the derived haplotype (371delACA, 494T), which is present at high frequencies in most non-African populations could be interpreted as either a result of migration followed by simple genetic drift or alternatively as positive selection acting on the derived alleles. The latter hypothesis seems likely, because there is evidence of strong positive selection acting on the USP26 gene.

Recent advances in the evolutionary genetics of sex determination indicate that the only molecular similarity in sex determination found so far among phyla is between the fly doublesex, worm mab-3 and vertebrate DMRT1(dsx- and mab3-related transcription factor 1) /DMY genes. Each of these factors encodes a zinc-finger-like DNA-binding motif, DM domain. Insights into the evolution and functions of human DMRT1 gene could reveal evolutionary mechanisms of sexual development. Here we report the identification and characterization of multiple isoforms of human DMRT1 in the testis. These transcripts encode predicted proteins with 373, 275 and 175 amino acids and they were generated by alternative splicing at 3' region. Expression level of DMRT1a is higher than those of both DMRT1b and c, and the DMRT1c expression was the lowest in testis, based on comparisons of mean values from real-time fluorescent quantitative RT-PCR analysis. Both DMRT1b and c result from exonization of intronic sequences, including the exonization of an Alu element. A further search for Alu elements within the DMRT1 gene demonstrated that all 99 Alu elements are non-randomly distributed among the non-coding regions on both directions. These new characteristics of DMRT1 would have an important impact on the evolution of sexual development mechanisms.

The detailed analysis of the Y chromosome in men with azoospermia or severe oligozoospermia has resulted in the identification of three regions of the long arm of the human Y chromosome, termed AZFa, AZFb and AZFc, (AZF: AZoospermia Factor) that are currently deleted in men with otherwise unexplained spermatogenic failure. Screening for these deletions is now common in many infertility centres and in some instances they have a prognostic relevance. Recently, attention has turned to partial deletions of the AZFc region. At first sight some of these deletions appear to have little effect on fertility, whilst others appear to be associated with significant risk for developing spermatogenic failure. However, the relationship between these partial AZFc deletions, reduced sperm counts and infertility is the subject of a continuing intense debate. There is a pressing need to clarify the impact of partial AZFc deletions on human spermatogenesis. This requires large-scale studies on well-characterized normospermic and oligo/azoospermic individuals of different ethnic origins with multiple informative AZFc markers if the correlation between these deletions and the phenotype is finally to be resolved. The definition of Y chromosome variants (haplotypes) in cases of partial AZFc deletions is likely to play an essential role in understanding the contribution of the deletion to reduced sperm counts.

The identification of new bovine male-specific DNA sequences is of great interest because the bovine Y chromosome remains poorly characterized in terms of physical and genetic maps. Since taurine and zebu Y chromosomes are structurally different, the identification of Y-specific sequences present in both sub-species is particularly important: these sequences are of evolutionary significance and can be broadly used for embryo sexing. In this work, we initially used the random amplified polymorphic DNA (RAPD) technique to search for male-specific sequences present as monomorphic markers in genomic DNA from zebu and taurine bulls. A male-specific RAPD band was found to be present and highly conserved in both sub-species, as demonstrated by Southern blotting, fluorescent in situ hybridization (FISH) and DNA sequencing. In a previous work, a pair of primers derived from this marker was successfully used in taurine and zebu embryo sexing.

Analysis of mtDNA and Y-chromosome variation in the Indo-Gangetic plains shows that it was a region where genetic components of different geographical origins (from west, east and south) met. The genetic architecture of the populations now living in the area comprise genetic components dating back to different time-periods during the Palaeolithic and the Neolithic. mtDNA data analysis has demonstrated a number of deep-rooting lineages of Pleistocene origin that may be witness to the arrival of the first settlers of South and Southwest Asia after humans left Africa around 60,000 YBP. In addition, comparisons of Y-chromosome and mtDNA data have indicated a number of recent and sexually asymmetrical demographic events, such as the migrations of the Parsis from Iran to India, and the maternal traces of the East African slave trade.

BACKGROUND: The Tyr978X BRCA1 mutation is a founder mutation detected in high-risk Iraqi-Iranian Jewish families as well as in the general non-Ashkenazi population. The same mutation was also reported in non-Jewish high-risk women from Canada. Its occurrence in non-Jewish individuals from Iran has never been tested. OBJECTIVE: Assess the occurrence rate of Tyr978X BRCA1 germline mutation in the general population of Iranian non- Jewish individuals and compare the BRCA1-linked haplotype of Jewish and non-Jewish mutation carriers. METHODS: PCR amplification of the relevant fragment of the BRCA1 gene, followed by restriction enzyme digestion that differentiates wild type from mutant allele. For haplotyping, 7 BRCA1-linked markers were used. The tested population included 442 apparently healthy Iranian non-Jewish individuals, and 17 mutation carriers from Israel and Canada. RESULTS: The Tyr978X BRCA1 mutation was not detected in any Iranian non-Jewish individual. The intragenic haplotype of all Jewish Israeli mutation carriers was identical, but differed from that of Canadian non-Jews in two intragenic markers. CONCLUSIONS: The Tyr978X BRCA1 mutation which is a founder mutation in Jews, may be a hot spot in non-Jewish high risk women, and probably does not represent a rare sequence variant in Iranian non-Jews.

A mosaic karyotype consisting of a 45,X cell line and a second cell line containing a normal or an abnormal Y chromosome is relatively common and is associated with a wide spectrum of clinical phenotypes. The aim of this study was to investigate patients with such a mosaic karyotype for Y chromosome material loss and then study the possible association of the absence of these regions with the phenotype, diagnosis, and Y-chromosome instability. We studied 17 clinically well-characterized mosaic patients whose karyotype consisted of a 45,X cell line and a second cell line containing a normal or an abnormal Y chromosome. The presence of the Y chromosome centromere was verified by fluorescence in situ hybridization (FISH) and was then characterized by 44 Y-chromosome specific-sequence tagged site (STS) markers. This study identifies a high frequency of Yq chromosome deletions (47%). The deletions extend from interval 5 to 7 sharing a common deleted interval (6F), which overlaps with the azoospermia factor region (AZF) region. This study finds no association between Y-chromosome loci hosting genes other than SRY, and the phenotypic sex, the diagnosis, and the phenotype of the patients. Furthermore, this study shows a possible association of these deletions with Y-chromosome instability.