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.     

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.     

Characterization of deletions at 9p affecting the candidate regions for sex reversal and deletion 9p syndrome by MLPA

The distal region on the short arm of chromosome 9 is of special interest for scientists interested in sex development as well as in the clinical phenotype of patients with the 9p deletion syndrome, characterized by mental retardation, trigonocephaly and other dysmorphic features. Specific genes responsible for different aspects of the phenotype have not been identified. Distal 9p deletions have also been reported in patients with 46,XY sex reversal, with or without 9p deletion syndrome. Within this region the strongest candidates for the gonadal dysgenesis phenotype are the DMRT genes; however, the genetic mechanism is not clear yet. Multiple ligation-dependent probe amplification represents a useful technique to evaluate submicroscopic interstitial or distal deletions that would help the definition of the minimal sex reversal region on 9p and could lead to the identification of gene(s) responsible of the 46,XY gonadal disorders of sex development (DSD). We designed a synthetic probe set that targets genes within the 9p23-9p24.3 region and analyzed a group of XY patients with impaired gonadal development. We characterized a deletion distal to the DMRT genes in a patient with isolated 46,XY gonadal DSD and narrowed down the breakpoint in a patient with a 46,XY del(9)(p23) karyotype with gonadal DSD and mild symptoms of 9p deletion syndrome. The results are compared with other patients described in the literature, and new aspects of sex reversal and the 9p deletion syndrome candidate regions are discussed.     

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.     

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.     

Pure XX gonadal dysgenesis in identical twins

Pure gonadal dysgenesis has been described in several sibships. We report a pair of monozygous twins and their younger sister with secondary amenorrhea. They had no associated congenital anomalies. Plasma FSH levels were elevated and the ovarian biopsies showed absence of follicular structures. Their karyotypes were 46XX, further supporting the concept that this form of familial gonadal dysgenesis is an autosomal recessive defect.     

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.     

XY gonadal dysgenesis associated with hGH and gonadotrophin deficiencies

A girl of remarkably short stature, referred for investigation with the diagnosis of gonadal dysgenesis and the finding of a male karyotype, proved to be deficient in growth hormone and gonadotrophin secretion, and was treated with growth and sex hormones. It was concluded that this case demonstrates an apparently casual coincidence of pituitary insufficiency with XY gonadal dysgenesis, evidently the first to be reported.     

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.     

Sex reversal in a child with the karyotype 46, XY, dup (1) (p22.3p32.3)

The karyotype 46,XY, dup(l) (p22.3p32.3) was found in a 10-year-old patient with sex reversal, mental retardation and multiple dysmorphic features. In other cases with duplication 1p but different breakpoints cryptorchidism and genital ambiguity have been observed suggesting the dosage effect of a locus in 1p involved in sex differentiation     

新发睾丸决定基因SRY突变导致46,XY性发育异常三例

目的在46,XY性发育异常疾病(46,XY DSD)患者中进行SRY突变检测,分析其发生频率,并总结检出SRY突变患者的临床特点。方法纳入2009-2014年在北京协和医院内分泌科就诊的46,XY DSD患者63例,收集详细临床资料,提取外周血基因组DNA,PCR特异性扩增SRY并进行Sanger测序,通过与在线数据库比对确定突变,分析临床特点。结果 63例患者中共有三例检出SRY的3种新突变(约5%)。这三例患者社会性别均为女性,染色体核型为46,XY,有阴道和子宫结构,性激素符合高促性腺激素性性腺功能减退症。3种突变分别为:Pro131His、R76C和L35Afs*25。前2种错义突变位点位于HMG box核定位信号区,累及高度保守氨基酸,后1种为移码突变导致HMG box缺失,均严重破坏了SRY蛋白的重要功能结构域。结论该研究发现的3种SRY新突变是导致46,XY DSD的病因,SRY突变的检出率约为5%;对于46,XY DSD患者,建议均行SRY检测以明确病因。     

Partial 9p monosomy in a girl with a tdic(9p23;13p11) translocation,minor anomalies,obesity, and mental retardation

We report on a case with a partial monosomy for the regions 9p23 → pter and 13p11 → pter as a result of a de novo translocation (9p23;13p11). The patient, a 16-year-old girl, has mental deficiency, obesity, and minor anomalies, including trigonocephaly, hypertelorism and a short, broad neck. Cytogenetic and microsatellite marker analysis allowed us to assign the breakpoint to the chromosomal region 9p23, flanked by the markers D9S144 and D9S157. In an attempt to establish a phenotype-genotype correlation, the clinical manifestations present in our patient are compared to those with partial 9p monosomy and breakpoint in p23, referred to in the literature. Am. J. Med. Genet. 71:139–143, 1997. © 1997 Wiley-Liss, Inc.     

Mixed gonadal dysgenesis and sex chromosome mosaicism with multiple cell lines including structural aberrations of the Y chromosome

A case of mixed (asymmetric) gonadal dysgenesis is reported in a girl with ambiguous external genitalia, a right intra-abdominal testis, a left streak gonad containing follicle-like structures devoid of oocytes and bilateral Mullerian derivatives. Buccal smear cells were X-chromatin negative and a Y-chromatin body was present in 31% of cells. Cytogenetic studies in peripheral blood leucocyte cultures showed sex chromosome mosaicism with cell lines including structural abnormalities of the Y chromosome in 36% of the cells: 45, X/46, XY/46, X, + i(Yp)/46, X, + Yq–/47, XYY/47, XY + Yq-.     

Gonadal dysgenesis in del(18p) syndrome

We report on a girl with syndromal gonadal dysgenesis and a de novo del(18p). Genetic factors controlling gonadal development are located not only on the X chromosome, but also on autosomes. The present case suggests that one of these genes is situated on 18p. We conclude that patients with del(18p) syndrome should be evaluated for gonadal dysgenesis. © 1995 Wiley-Liss, Inc.     

Mixed gonadal dysgenesis and cell line differentiation. Case presentation and literature review

A male patient with mixed gonadal dysgenesis, involving a streak gonad on the right and a histologically normal testis in the left, was found to have a 45, X/46, X, dic(Yp) chromosome constitution on peripheral blood cultures. Fibroblasts grown from both gonads showed the "normal" testicular tissue to have e 45, X/46, X, dic(Yp), whereas the cells from the streak gonad were all 45, X. The structure of the dic(Yp) chromosome was confirmed using non-isotopic in situ hybridization with Y centromere and Yp specific probes. On hormonal stimulation, testosterone levels rose by 50%. The "normal" testis was left in situ , but close follow up will be required in view of the malignant potential.     

Complete XY gonadal dysgenesis and aspects of the SRYgenotype and gonadal tumor formation

 XY gonadal dysgenesis can be classified as either complete or incomplete according to gonadal morphology. The disease is a sex-reversal disorder resulting from embryonic testicular regression sequences and is induced by mutations in the sex-determining region Y (SRY) gene. The incidence of SRY mutations is thought to be approximately 20%. As the disease is characterized by a frequent complication of gonadal tumors, patients are usually advised to undergo prophylactic gonadectomy. In this study, we searched for mutations in SRY open reading frames from three patients with the complete form of XY gonadal dysgenesis, and detected missense mutations in two patients. Combined with the results of our previous study, in which SRY abnormalities were also detected in two out of three complete-type patients, the final incidence of SRY abnormalities was 67% (four of six patients), which is much higher than previously thought. The incidence of gonadal tumor formation in patients with SRY abnormalities was 50% (two of four patients), which is similar to the result of a metanalysis of patients with SRY abnormalities that revealed an incidence of 52.5%. Therefore, it is possible that the lower incidences of SRY abnormalities previously reported were caused by the inclusion of patients with the incomplete form or other sex-reversal disorders. Moreover, our results suggest that clinicians should carefully examine patients with SRY abnormalities. Received: December 5, 2001 / Accepted: March 4, 2002     

Complex de novo rearrangement of chromosome 9 with clinical features of monosomy 9p syndrome

A girl with a complex rearrangement of chromosome 9 is reported. She shows the characteristic clinical features of monosomy 9p syndrome. The rearrangement was apparently preceded by four breaks which resulted in a presumptive tiny deletion of the distal end of the short arm, inversion of the rest of this arm and a proven deletion of the secondary constriction region of the long arm. By means of C-banding, it was possible to demonstrate the paternal origin of the rearranged chromosome 9. Finally, it is shown that the region determining the phenotypic expression of monosomy 9p syndrome is seemingly located at band 9p24.