Mapping a gene for 46,XY gonadal dysgenesis by linkage analysis

46,XY gonadal dysgenesis was transmitted as an autosomal-dominant trait in a large family with multiple affected members. Expressivity of the trait was highly variable, ranging from pure to partial gonadal dysgenesis associated with normal female genitalia or sexual ambiguity, to mild hypospadias in otherwise normal males. The phenotypic features of this trait appeared to be confined to the genitourinary system. Multipoint parametric analysis using markers D5S664, D5S633, and D5D2102 yielded an LOD score of 4.47, assuming sex-limited, autosomal-dominant inheritance with a penetrance of 0.6. Because mutation in testis-determining genes leads to gonadal dysgenesis in 46,XY individuals, we postulate that the gene mapped by this study normally plays a role in gonadal differentiation.     

46,XY pure gonadal dysgenesis with non-fluorescent Y chromosome

A 46,XY karyotype with a non-fluorescent Y chromosome was found in an infantile girl aged 16 with primary amenorrhea. Identification of the Y chromosome was made by different staining techniques and a photometric scanning method. The histology of the streak gonad also indicated the Y character of the chromosome. The authors' interpretation is a 46,XY pure gonadal dysgenesis with a non-fluorescent Y chromosome.     

Probable autosomal dominant infantile pyloric stenosis in a large kindred

The proposita was operated on in this hospital in 1980 for pyloric stenosis, at the age of 13 days, after vomiting had started 5 days previously, and the diagnosis had been confirmed on radiological investigation. Her older sister and two male cousins of the father had the same operation in Israel in infancy. The other nine affected individuals in the family were known to have had projectile vomiting for several months in infancy, and two of them died in infancy. They were all born in the Jewish community in Georgia, U.S.S.R. The male:female sex ratio was 2:2 for the operated cases, and 4:5 for those with projectile vomiting history. There was no skipping of a generation. This family indicates that pyloric stenosis can exceptionally be inherited as a simple autosomal dominant trait.     

Lecithin-cholesterol-acyltransferase deficiency: autosomal recessive transmission in a large kindred*

Thirty-four members of a single Sardinian kindred with lecithin-cholesterol-acyltransferase deficiency have been studied. The kindred spans four generations and the parents of the two affected siblings are blood relatives. Segregation of the acyltransferase deficiency gene in the family clearly demonstrated an autosomal recessive mode of inheritance. Thirteen family members, including all obligate heterozygotes, had roughly half-normal acyltransferase activities (mean ± S.D. = 0.39 ± 0.06 mU/ml) when compared to 17 intrafamilial controls and spouses (mean ± S.D. = 0.72 ± 0.09 mU/ml) and 40 blood donors from Marburg/Lahn (mean ± S.D. = 0.76 ±0.1 mU/ml). Characterization of the heterozygotes did not reveal abnormalities in their plasma lipoproteins. LCAT deficiency and the β-thalassaemia trait coexisting in this kindred segregated independently.     

Gonadal dysgenesis in a 46,XY female mosaic for double autosomal trisomies 8 and 21.

The proband was evaluated at 19 years of age because of primary amenorrhoea and, on chromosomal analysis, was found to have a 46,XY karyotype in 75% of her cells and 48,XY, +8, +21 in 25% of her cells. She appeared normal at birth and exhibited normal intellectual and physical development until puberty when secondary sexual differentiation failed. This young women showed none of the dysmorphic features associated with either trisomy 8 or trisomy 21. Her XY gonadal dysgenesis was manifested by late developmental problems of amenorrhoea, sexual infantilism, and gonadal neoplasia.     

Metaphyseal dysplasia: a new autosomal dominant type in a large German kindred

We describe a new autosomal dominant type of metaphyseal dysplasia (MD) in five generations of a German kindred. The main characteristics are metaphyseal widening and undermodeling of the tubular bones with Erlenmeyer flask-like appearance of the distal femora (typical of MD), with unusually severe varus deformity of the radii and flat exostoses of the long bones localized in the metaphyses. The skull is unaffected. Allelism with craniometaphyseal dysplasia (CMD) was excluded by linkage analysis.     

Association of deletion 9p, 46,XY gonadal dysgenesis and autistic spectrum disorder

Deletions of distal chromosome 9p24 are often associated with 46,XY gonadal dysgenesis and, depending on the extent of the deletion, the monosomy 9p syndrome. We have previously noted that some cases of 46,XY gonadal dysgenesis carry a 9p deletion and exhibit behavioural problems consistent with autistic spectrum disorder. These cases had a small terminal deletion of 9p with limited or no somatic anomalies that are characteristic of the monosomy 9p syndrome. Here, we present a new case of 46,XY partial gonadal dysgenesis and autistic spectrum disorder associated with a de novo deletion of 9p24 that was detected by ultra-high resolution oligo microarray comparative genomic hybridization. The deletion included the candidate sex-determining genes in the region DMRT1 and DMRT3. These data suggest that a gene responsible for autistic spectrum disorder is located within 9p24. It remains to be determined if the gonadal dysgenesis and autistic spectrum disorder are caused by a single gene or if they are caused by distinct genetic entities at 9p24.     

Pathogenic variants in the DEAH-box RNA helicase DHX37 are a frequent cause of 46,XY gonadal dysgenesis and 46,XY testicular regression syndrome

PurposeXY individuals with disorders/differences of sex development (DSD) are characterized by reduced androgenization caused, in some children, by gonadal dysgenesis or testis regression during fetal development. The genetic etiology for most patients with 46,XY gonadal dysgenesis and for all patients with testicular regression syndrome (TRS) is unknown.MethodsWe performed exome and/or Sanger sequencing in 145 individuals with 46,XY DSD of unknown etiology including gonadal dysgenesis and TRS.ResultsThirteen children carried heterozygous missense pathogenic variants involving the RNA helicase DHX37, which is essential for ribosome biogenesis. Enrichment of rare/novel DHX37 missense variants in 46,XY DSD is highly significant compared with controls (P value = 5.8 × 10⁻¹⁰). Five variants are de novo (P value = 1.5 × 10⁻⁵). Twelve variants are clustered in two highly conserved functional domains and were specifically associated with gonadal dysgenesis and TRS. Consistent with a role in early testis development, DHX37 is expressed specifically in somatic cells of the developing human and mouse testis.ConclusionDHX37 pathogenic variants are a new cause of an autosomal dominant form of 46,XY DSD, including gonadal dysgenesis and TRS, showing that these conditions are part of a clinical spectrum. This raises the possibility that some forms of DSD may be a ribosomopathy.     

Novel candidate genes for 46,XY gonadal dysgenesis identified by a customized 1 M array-CGH platform

Half of all patients with a disorder of sex development (DSD) do not receive a specific molecular diagnosis. Comparative genomic hybridization (CGH) can detect copy number changes causing gene haploinsufficiency or over-expression that can lead to impaired gonadal development and gonadal DSD. The purpose of this study was to identify novel candidate genes for 46,XY gonadal dysgenesis (GD) using a customized 1 M array-CGH platform with whole-genome coverage and probe enrichment targeting 78 genes involved in sex development. Fourteen patients with 46,XY gonadal DSD were enrolled in the study. Nine individuals were analyzed by array CGH. All patients were included in a follow up sequencing study of candidate genes. Three novel candidate regions for 46,XY GD were identified in two patients. An interstitial duplication of the SUPT3H gene and a deletion of C2ORF80 were detected in a pair of affected siblings. Sequence analysis of these genes in all patients revealed no additional mutations. A large duplication highlighting PIP5K1B, PRKACG and FAM189A2 as candidates for 46,XY GD, were also detected. All five genes are expressed in testicular tissues, and one is shown to cause gonadal DSD in mice. However detailed functional information is lacking for these genes.     

Embryonic testicular regression sequence: A part of the clinical spectrum of 46, XY gonadal dysgenesis

With the identification of the cystic fibrosis (CF) gene and its major mutations in 1989, there has been considerable debate among health professionals as to whether population-based carrier testing should be instituted. This paper presents the results of a survey to determine the attitudes of physicians and genetics professionals towards CF carrier testing. Factors associated with differences in attitudes also were examined. A questionnaire was mailed to primary care physicians and psychiatrists in 10 states who graduated from medical school between 1950 and 1985. For comparison, medical geneticists and genetic counselors in the same states also received the questionnaire. A total of 1,140 primary care physicians and psychiatrists (64.8%) and 280 medical geneticists and genetic counselors (79.1%) responded. Although 92% of respondents believed that a couple should be tested after asking about a test that detected 80% of carriers, only 43.9% of respondents believed such a test should be offered routinely. Those specialists most likely to have been involved in genetic services were most opposed to routine screening. The most important reason reported for opposition to routine screening was the consequences of an 80% detection rate. When presented with a hypothetical “error-free” test, 75.9% of respondents favored routine testing. Our findings suggest that there was little support for routinely offering the CF carrier test available at the time of this study among the physicians and professionals most involved in the provision of genetic services. © 1994 Wiley-Liss, Inc.     

46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism

Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.     

H-Y antigen in 46,XY pure testicular dysgenesis

Clinical, cytogenetic, pathologic and histocompatibility-Y (H-Y) antigen studies were performed on a phenotypic female with primary amenorrhea and streak gonads. Pathological examination of tissues removed at total hysterectomy and bilateral salpingo-gonadectomy showed gonadoblastoma and dysgerminoma of left streak. A single F-body (Y chromosome) was found in buccal smears. Analysis of blood cells and tumor fibroblasts showed a 46, XY chromosome constitution (Q-banding). The data were consistent with a diagnosis of 46, XY pure testicular dysgenesis. Positive results for H-Y antigen were found in this case.     

Carcinoma in situ, gonadoblastoma, and early invasive neoplasia in a nine-year-old girl with 46,XY gonadal dysgenesis.

Carcinoma in situ (CIS), gonadoblastoma, and early invasive neoplasia were detected in the dysgenetic gonad of a nine-year-old girl with 46,XY gonadal dysgenesis. A close relationship between the three neoplastic components was supported by morphological and immunohistochemical studies. Our findings support the hypothesis that all germ cell tumours, including gonadoblastomas, originate from CIS germ cells formed during early embryonic life.     

A 46,XY female with mixed gonadal dysgenesis and a 48,XY, +7, +i(12p) chromosome pattern in a primary gonadal tumor.

Cytogenetic analysis of a primary germ-cell tumor originating from the streak gonad of a 20-year-old phenotypic female with a 46,XY karyotype and mixed gonadal dysgenesis revealed a 48,XY, +7, +i(12p) chromosomal pattern. Germ-cell tumors originating from gonads of normal males are usually highly aneuploid. An isochromosome 12p as well as an overrepresentation of chromosome 7 material are among the specific changes most consistently observed. The present case shows that tumors of dysgenetic gonads, albeit being near-diploid, may exhibit similar chromosomal changes. This observation lends additional support to the hypothesis that these specific cytogenetic anomalies may play an important role in the pathogenesis of human germ-cell tumors.     

46,XX gonadal dysgenesis with epibulbar dermoid

Pure gonadal dysgenesis with 46,XX genotype is a rare abnormality with unknown etiology. Although sensorineural deafness has been described with 46,XX gonadal dysgenesis, the majority of reported cases of 46,XX gonadal dysgenesis have no associated physical abnormalities. We report a patient with 46,XX gonadal dysgenesis associated with epibulbar dermoids and preauricular skin tags, the classic ocular and skin manifestations of Goldenhar sequence (oculoauricular vertebral dysplasia). We propose that our patient may represent a new and previously unreported syndrome.     

Genetic heterogeneity of XY gonadal dysgenesis (Swyer syndrome): H-Y antigen-negative XY gonadal dysgenesis associated with inflammatory bowel disease

A 16 1/2-year-old girl was studied because of ileitis, lack of pubertal development, and primary amenorrhea. She had a 46,XY chromosome constitution in lymphocytes in fibroblasts without structural defects of X or Y. She was H-Y antigen negative. This observation supports the concept of causal heterogeneity of XY gonadal dysgenesis (Swyer syndrome). Two groups have been established: (1) H-Y antigen-positive forms, which are more common, possibly due to gonad-specific receptor defects (total failure or reduced receptor affinity), (2) H-Y antigen-negative forms possibly due to mutation in the H-Y generating system, either of the structural gene (presumably autosomal) or of a controlling gene (on the sex chromosomes). The H-Y antigen status may be of value in determining which patients are at risk for gonadoblastoma or dysgerminoma.     

H-Y antigen in 46,XY pure testicular dysgenesis.

Clinical, cytogenetic, pathologic, and histocompatibility-Y (H-Y) antigen studies were performed on a phenotype female with primary amenorrhea and streak gonads. Pathological examination of tissues removed at total hysterectomy and bilateral salpinog-gonadectomy showed gonadoblastoma and dysgerminoma of left streak. A single F-body (Y chromosome) was found in buccal smears. Analysis of blood cells and tumor fibroblasts showed a 46,XY chromosome constitution (Q-banding). The data were consistent with a diagnosis of 46,XY pure testicular dysgenesis. Positive results for H-Y antigen were found in this case.     

Linkage analysis in a large kindred with autosomal dominant transmission of polyglandular autoimmune disease type II (Schmidt syndrome)

Schmidt syndrome (PGA syndrome type II) is a rare condition characterized by polyglandular failure. It is an autosomal dominant trait with variable expressivity that was inherited over four generations in an the Indiana kindred. Association of HLA-B8 has been reported with Schmidt syndrome. Our proband is a 12-year-old boy with Addison disease, insulin dependent diabetes mellitus (IDDM), and vitiligo. Two of his eight sibs had either IDDM (sister) or vitiligo and hyperthyroidism (brother). His mother had hypothyroidism. Seven members of earlier generations apparently were also affected. We obtained peripheral blood for HLA and genetic analysis from 21 relatives in a family with 8 Schmidt syndrome individuals in three generations. HLA studies on 15 affected and unaffected relatives showed only 2 of 7 persons with B8-containing haplotypes. Therefore, no association exists between the B8-containing haplotype and the syndrome. We identified informative marker loci. No evidence for linkage of the Schmidt locus to any of the 14 markers was found and close linkage to esterase D and adenylate kinase and possibly properdin factor B was excluded.     

XY gonadal dysgenesis associated with a multiple pterygium syndrome phenotype

Most phenotypic females with an XY male karyotype do not have significant extra-genital anomalies; however, some patients with additional abnormalities have been described. We report on an individual with XY gonadal dysgenesis, mental retardation, microcephaly, growth retardation, and multiple pterygia. Although not previously reported, the possible relationship between these findings is discussed in the context of evident heterogeneity of XY gonadal dysgenesis. Am. J. Med Genet. 68:7–11, 1997 © 1997 Wiley-Liss, Inc.