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1.
2.
We report a successful second delivery of a healthy infant fathered using refrozen thawed testicular sperm from an infertile male chimera. We also examined sex chromosome distribution of the seminiferous tubule. Intracytoplasmic sperm injection (ICSI) was performed using the remaining refrozen testicular sperm, which had been stored during the first treatment. Biopsied testicular cells were examined by fluorescence in situ hybridization (FISH) and the peripheral lymphocyte karyotype was tested using a G-band. Following ICSI, a second pregnancy was established, and a healthy girl was successfully delivered at 40 gestational weeks without complications. Although the husband’s lymphocyte chromosomal analysis revealed a 46, XX [28]/46, XY [2] karyotype, the seminiferous tubule cells on histological examination by FISH were chimeric sex chromosome type XX [18]/XY [82]. In conclusion, this is a very rare case report of a successful subsequent delivery of a healthy infant (46, XX) from an infertile true hermaphrodite (46, XX/46, XY) using refrozen thawed testicular sperm. The seminiferous tubule cells’ karyotype ratio differed from that of the lymphocytes.  相似文献   

3.
Summary Some twenty cases of dispermic chimeras with the karyotype 46,XX/46,XY, discovered because of gonadal dysplasias or a true hermaphroditism, have been reported. This is a report of a phenotypically normal man with 46,XX/46,XY chimerism in whom a prepubertal finding of positive X-chromatin was interpreted as Klinefelter syndrome. The diagnosis was revised 11 years later when the family doctor, who doubted the earlier diagnosis because of the patient's normal-sized testes, sent him to an outpatient clinic. The young man was 23 years old, athletic (74kg, 180cm), with normal body proportions, normal sexual hair distribution, normal libido and potency, normal endocrine parameters, and a normal spermiogram. The karyotype revealed an XX/XY mosaic in a proportion of 1:2. An identical set of maternal markers (Q- and C-banding) was present in male and female cells. Differences were found with respect to two paternal markers. Furthermore, blood, serum, and red cell enzyme groups in five systems showed two phenotypes, again with duality of paternal origin. It is concluded that a positive X-chromatin in prepuperty, especially in the absence of supporting clinical features, must be followed by a karyotype study.  相似文献   

4.
True hermaphroditism usually appears with ambiguous genitalia requiring extensive evaluation during the neonatal period. There have been occasional cases with better differentiation of external genitalia, leading to delays in diagnosis. We report the case of an adolescent boy with true hermaphroditism who presented with normal external genitalia and no sexual ambiguity. He was referred due to progressive gynecomastia and arrest of puberty. He presented at the age of 16 years for gynecomastia of rapid progression with normal penile development and both gonads in scrotum and normal testosterone and increased gonadotropin levels. Gonadal ultrasound scan was compatible with testicular and ovarian tissues in scrotum, and the karyotype showed two cellular lines (46,XX/46,XY). Gonadal histology revealed bilateral ovotestes. A genotype polymerase chain reaction mediated analysis using seven microsatellite markers did not confirm chimerism. Clinical findings and mechanism of generation are discussed.  相似文献   

5.
Summary In an infant with gonadal dysgenesis and somatic anomalies, the internal and external genitalia were female but the gonads contained tubular structures suggesting male differentiation. The karyotype was 46,XY with no evidence of structural aberration or mosaicism. Hormonal metabolism and H-Y antigen expression were assayed in cultured gonadal cells. Although unable to synthesize testosterone, the cultured cells were able to convert it to dihydrotestosterone. H-Y antigen was present, perhaps at a level lower than that in cells from normal XY males. Our observations indicate that a modicum of testicular organogenesis may precede the involution that results in a streak gonad in some cases of gonadal dysgenesis.  相似文献   

6.
Summary The syndrome of 46,XX true hermaphroditism is a clinical condition in which both ovarian and testicular tissue are found in one individual. Both Mullerian and Wolffian structures are usually present, and external genitalia are often ambiguous. Two alternative mechanisms have been proposed to explain the development of testicular tissue in these subjects: (1) translocation of chromosomal material encoding the testicular determination factor (TDF) from the Y to the X chromosome or to an autosome, or (2) an autosomal dominant mutation that permits testicular determination in the absence of TDF. We have investigated five subjects with 46,XX true hermaphroditism. Four individuals had a normal 46,XX karyotype; one subject (307) had an apparent terminal deletion of the short arm of one X chromosome. Genomic DNA was isolated from these individuals and subjected to Southern blot analysis. Only subject 307 had Y chromosomal sequences that included the pseudoautosomal boundary, SRY (sex-determining region of Y), ZFY (Y gene encoding a zinc finger protein), and DXYS5 (an anonymous locus on the distal short arm of Y) but lacked sequences for DYZ5 (proximal short arm of Y) and for the long arm probes DYZ1 and DYZ2. The genomic DNA of the other four subjects lacked detectable Y chromosomal sequences when assayed either by Southern blotting or after polymerase chain reaction amplification. Our data demonstrate that 46,XX true hermaphroditism is a genetically heterogeneous condition, some subjects having TDF sequences but most not. The 46,XX subjects without SRY may have a mutation of an autosomal gene that permits testicular determination in the absence of TDF.  相似文献   

7.
Males with the 45,X/46,XY karyotype and malformations of the external genitalia carry an increased risk of developing germ cell neoplasia of the gonads. We have studied gonadal tissue from 10 individuals, 0.3-17 years of age, with a male phenotype and either hypospadias and/or cryptorchidism. Four patients, 0.3-15 years of age, had carcinoma in situ, 1 boy had Sertoli-cell-only pattern and the remainder prepubertal histology. Gonadoblastoma or invasive carcinoma was not found. On the basis of our current knowledge we propose a strategy for management and follow-up of these boys in order to detect possible premalignant histological changes early and prevent development of a gonadal tumour.  相似文献   

8.
True hermaphroditism (TH) is an unusual form of sex reversal, characterized by the development of testicular and ovarian tissue in the same subject. Approximately 60% of the patients have a 46,XX karyotype, 33% are mosaics with a second cell line containing a Y chromosome, while the remaining 7% are 46,XY. Molecular analyses have demonstrated that SRY is present in only 10% of TH with a 46,XX karyotype; therefore, in the remaining 90%, mutations at unknown X-linked or autosomal sex determining loci have been proposed as factors responsible for testicular development. True hermaphroditism presents considerable genetic heterogeneity with several molecular anomalies leading to the dual gonadal development as SRY point mutations or SRY hidden gonadal mosaicism. In order to identify genetic defects associated with subjects with the disease, we performed molecular analyses of the SRY gene in DNA from blood leukocytes and gonadal tissue in 12 true hermaphrodites with different karyotypes. Our results using PCR and FISH analyses reveal the presence of hidden mosaicism for SRY or other Y sequences in some patients with XX true hermaphroditism and confirms that mosaicism for SRY limited to the gonads is an alternative mechanism for testicular development in 46,XX true hermaphrodites.  相似文献   

9.
The prognosis for 45,X/46,XX mosaicism diagnosed prenatally has yet to be established. We report our experience with 12 patients in whom prenatal diagnosis of 45,X/46,XX mosaicism was detected by amniocentesis for advanced maternal age or decreased maternal serum alpha-feto protein and compared them with 41 45,X/46,XX patients diagnosed postnatally. The girls in the prenatal group range in age from 3 mo to 10 years. All have had normal linear growth. Four had structural anomalies including: ASD (n = 1); ptosis and esotropia (n = 1); labial fusion (n = 1); and urogenital sinus, dysplastic kidneys, and hydrometrocolpos (n = 1). Gonadotropins were measured in seven; one had elevated luteinizing hormone/FSH at 3 mo of age. One has developmental delay and seizures as well as ophthalmologic abnormalities. None would have warranted karyotyping for clinical suspicion of Turner syndrome. The prevalence of 45,X/46,XX mosaicism is 10-fold higher among amniocenteses than in series of postnatally diagnosed individuals with Turner syndrome, which suggests that most individuals with this karyotype escape detection and that an ascertainment bias exists toward those with clinically evident abnormalities. The phenomenon of a milder phenotype for the prenatal group is similar to that observed for 45,X/46,XY diagnosed prenatally. Prenatal counseling for 45,X/46,XX in the absence of such ultrasound abnormalities as hydrops fetalis should take into account the expectation of a milder phenotype (except, possibly, with respect to developmental delay) than that of patients ascertained postnatally. The same does not hold true for 45,x diagnosed prenatally.  相似文献   

10.
The sex-determining region of Chr Y (Sry) gene is sufficient to induce testis formation and the subsequent male development of internal and external genitalia in chromosomally female mice and humans. In XX sex-reversed males, such as XX/Sry-transgenic (XX/Sry) mice, however, testicular germ cells always disappear soon after birth because of germ cell-autonomous defects. Therefore, it remains unclear whether or not Sry alone is sufficient to induce a fully functional testicular soma capable of supporting complete spermatogenesis in the XX body. Here, we demonstrate that the testicular somatic environment of XX/Sry males is defective in supporting the later phases of spermatogenesis. Spermatogonial transplantation analyses using XX/Sry male mice revealed that donor XY spermatogonia are capable of proliferating, of entering meiosis and of differentiating to the round-spermatid stage. XY-donor-derived round spermatids, however, were frequently detached from the XX/Sry seminiferous epithelia and underwent cell death, resulting in severe deficiency of elongated spermatid stages. By contrast, immature XY seminiferous tubule segments transplanted under XX/Sry testis capsules clearly displayed proper differentiation into elongated spermatids in the transplanted XY-donor tubules. Microarray analysis of seminiferous tubules isolated from XX/Sry testes confirmed the missing expression of several Y-linked genes and the alterations in the expression profile of genes associated with spermiogenesis. Therefore, our findings indicate dysfunction of the somatic tubule components, probably Sertoli cells, of XX/Sry testes, highlighting the idea that Sry alone is insufficient to induce a fully functional Sertoli cell in XX mice.  相似文献   

11.
True hermaphroditism in humans usually is associated with a 46,XX karyotype or with mosaicism in which admixtures of cells with an XX and an XY karyotype are seen. However, the mechanisms that cause such mosaicisms are poorly understood. To date, with rare exceptions, analyses of hermaphrodites have been limited mostly to cytogenetic investigations. In this report, we describe a 5-year-old patient with true hermaphroditism and a 46,XX/46,XY karyotype (ratio 38:12) in lymphocytes, suggesting involvement of two fertilization events. Microsatellite DNA polymorphisms distributed throughout the genome were analyzed, to investigate the origin of the cell lines concerned. The results are consistent with double paternal and single maternal genetic contributions. Possible mechanisms that would explain these findings are discussed. The most likely mechanism involves a single haploid ovum dividing parthenogenetically into two haploid ova, followed by double fertilization and fusion of the two zygotes into a single individual, at the early embryonic stage.  相似文献   

12.
Summary We documented a new case of chi 46,XX/46,XY true hermaphroditism substantiated by the evaluation of chromosomal heteromorphism in banded preparations. The patient, a 12-year-old Japanese boy with ambiguous external genitalia, was seen because of abnormal breast development. Surgical exploration showed the right gonad to be an ovotestis and the left gonad to be an ovary. Cytogenetic studies revealed cell admixtures of 46,XX and 46,XY karyotypes in peripheral lymphocytes, skin fibroblasts, and gonadal fibroblasts. From the pedigree studies, the paternal double genetic contributions were evidenced by the differences of sex chromosomes and the blood group types for the ABO and MNSs systems in the two cell lines of the patient. The maternal double genetic contributions were confirmed by the inheritance of Q-fluorescent markers on chromosomes 13 and 22 and by alleles for the Kidd blood group system.  相似文献   

13.
Familial expression of inadequate virilization of 46XY siblings is often reported as an isolated anomaly. We recently evaluated two families with 2 siblings who had a 46XY karyotype, ambiguous genitalia or micropenis, facial anomalies and mental retardation. There is no evidence of gonadotropin deficiency, defects of steroidogenesis, or androgen insensitivity. While there was a testosterone response to human chorionic gonadotropin stimulation in all 3 tested, gonadotropin levels were elevated in 2 of the infants suggestive of faulty seminiferous tubules, 1 of whom later had elevated luteinizing hormone levels. These kindreds may represent a new syndrome with either an X-linked recessive or sex-limited autosomal dominant form of inheritance, with partial testicular failure, multiple congenital anomalies, and mental retardation.  相似文献   

14.
Summary Presence of H-Y antigen has been correlated with testicular differentiation, and absence of H-Y with failure of testicular differentiation, in a variety of mammalian species. To determine more precisely the relationship between expression of H-Y antigen and development of the testis, we studied the cells of phenotypic females with the 46,XY male karyotype. Blood leukocytes were typed H-Y+ in five XY females with gonadal dysgenesis, although in other studies blood leukocytes from XY females with gonadal dysgenesis were typed H-Y-. Thus mere presence of H-Y antigen is not sufficient to guarantee normal differentiation of the testis. In the present paper we review evidence for an additional factor in gonadal organogenesis, the H-Y antigen receptor. We infer that testicular development requires engagement of H-Y and its receptor. It follows that XY gonadal dysgenesis is the consequence of functional absence of the H-Y testis inducer as in the following conditions: failure of synthesis of H-Y or failure of specific binding of H-Y.  相似文献   

15.
Mixed gonadal dysgenesis (MGD) is an abnormality of sexual differentiation (ASD), which encompasses an heterogeneous group of different gonadal and phenotypic abnormalities. This study describes the main clinical features found in 16 patients with MGD, relating the clinical presentation with cytogenetic evaluation and histopathological findings. For purpose of this study, MGD was considered in those patients who fulfilled the following diagnostic criteria: 1) müllerian and/or wolfflan derivatives; 2) any of the following gonadal characteristics: a) bilateral intrabdominal or scrotal immature testicular tissue; b) intrabdominal or scrotal immature testicular tissue with contralateral streak gonad. Patients were selected from an ASD study which was carried out in Medical Genetic Unit of University of Zulia (UGM-LUZ), Maracaibo, Venezuela, from 1980 to 1997. The following information was extracted from the medical history at UGM-LUZ: age, gender which patient was reared, clinical presentation, cytogenetic evaluation, laparoscopic findings and gonadal biopsy. Sixteen patients fulfilled the diagnostic criteria and ranged in age from 1.2 to 39.4 years with an average of 12.65 years. Only 5 patients were reared as males. Twelve patients consulted for genital ambiguity. Chromosomal evaluation was as following: 8 patients with 45,X/46,XY mosaicism: 5 had a 46,XY normal male karyotype and the remaining patients: 46,XX; 46,XX/46,XY and 45,X/46,Xi(Xq) karyotypes, respectively. All patients showed müllerian derivatives and occasionally wolffian derivatives. Gonadal tumors were present in 2 patients. Molecular studies of genes that govern gonadal development are necessary for a better understanding of the wide heterogeneity present in MGD.  相似文献   

16.
A case of male hermaphroditism is presented. It complied with all traditional criteria of male hermaphroditism due to Leydig's cells hypoplasia (anomaly of the internal genitalia, karyotype 46, XY, presence of the testicular tissue, no response of the hypoplastic Leydig's cells to HCG stimulation with simultaneous dramatic decrease in their number in the interstitial tissue. Emphasis is on the marked difference in incomplete virilization of the external genitalia related to the occurrence of Leydig's cells insufficiency.  相似文献   

17.
A 35-year-old male was investigated for primary infertility. Clinical examination showed an intelligent man with normal facial appearance and moustache and small firm testes. Testicular histopathology revealed marked atrophy of the testes with no spermatogenesis and absence of germ cells. Hormonal profile showed elevated levels of FSH,LH and low levels of testosterone. Chromosome analysis from whole blood culture showed cells with 46,XX/46,XY/47,XXY/48,XXXY/48,XXYY mosaicism. The predominant cell line was 47,XXY (87.86%). 46,XY/47,XXY mosaicism is not uncommon. However, mosaicism of multiple sex chromosome aneuploidy is rarely observed. This is the first report of mosaicism in Klinefelter's syndrome variant with five cell lines.  相似文献   

18.
Congenital lipoid adrenal hyperplasia (lipoid CAH) is the most severe form of CAH in which the synthesis of all gonadal and adrenal cortical steroids is markedly impaired. Lipoid CAH may be caused by the defect in either the steroidogenic acute regulatory (StAR) protein or the P450scc. More than 34 different mutations in StAR gene have been identified. Clinically, most of the patients manifest adrenal insufficiency from 1 day to 2 months of age, but some patient show delayed onset of adrenal insufficiency. Affected 46, XY subjects do not show pubertal development, whereas affected 46, XX subjects undergo spontaneous feminization, breast development and cyclical vaginal bleeding at the usual age of puberty.

X-linked adrenal hypoplasia congenital (AHC) is a rare congenital adrenal disorder characterized by severe adrenal insufficiency and hypogonadotropic hypogonadism. More than 80 different several intragenic mutations of DAX-1 have been identified. The failure of pubertal development may be caused by either abnormal hypothalamic or pituitary regulation of gonadotropin secretion. In addition, although the testicular steroidogenesis is largely intact, the functional maturity of Sertoli cells and also spermatogenesis are impaired. The type of mutation does not predict clinical phenotype. Thus, unified mechanism how DAX-1 gene defect gives rise to adrenal insufficiency, hypothalamic/pituitary hypogonadism and impaired spermatogenesis remains established.  相似文献   


19.
Chromosomal mosaicism in prenatal diagnosis is an important problem to be solved immediately and the probable phenotypic reflections should be explained to the family. We report two numerical and two structural mosaicisms detected in amniocyte cultures. The first fetus had a 47,XY,+mar[10]/46,XY[10] karyotype. The marker chromosome was shown to be derived from chromosome 15 by FISH method. The newborn had intrauterine growth retardation and cerebral thrombosis and died at the 29th day of age. The second fetus had a 45,X[4]/46,XX[26] karyotype. The parents refused cordocentesis and decided to terminate pregnancy in the 21st week. The third case, presented with bilateral large choroid plexus cysts, had a 46,XX, dup(1)(q22-q32)[9]/46,XX[21] karyotype. The parents' karyotypes were normal and the pregnancy was aborted in the 23rd week of gestation. The second structural abnormality was reported as 46,XX,t(6;11)(q23; p13)[3]/46,XX[20]. The mosaicism was detected in only one flask. The parents decided to continue pregnancy and cordocentesis could not be performed due to the fetal and placental position. The baby was born at term. Peripheral blood lymphocyte culture resulted in a 46,XX normal karyotype. Information and risks were explained to all families during genetic counseling. Mosaicism in prenatal diagnosis needs both detailed examination and follow up, since clinical findings depend on the type of abnormality.  相似文献   

20.
In mammals, a master gene located on the Y chromosome, the testis-determining gene SRY, controls sex determination. SRY protein is expressed in the genital ridge before testis determination, and in the testis it is expressed in Sertoli and germ cells. Completely sex-reversed patients are classified as either 46,XX males or 46,XY females. SRY mutations have been described in only 15% of patients with 46,XY complete or partial gonadal dysgenesis. However, although incomplete or partial sex-reversal affects 46,XX true hermaphrodites, 46,XY gonadal dysgenesis, and 46,XX/46,XY mosaicism, only 15% of the 46,XX true hermaphrodites analyzed have the SRY gene. Here, we demonstrate that the SRY protein is expressed in the tubules of streak gonads and rete testis, indicating that the SRY protein is normally expressed early during testis determination. Based on these results, we propose that some factors downstream from SRY may be mutated in these 46,XY sex-reversal patients. We have also analyzed SRY protein expression in the ovotestis from 46,XX true hermaphrodites and 46,XX/46,XY mosaicism, demonstrating SRY protein expression in both testicular and ovarian portions in these patients. This suggests that the SRY protein does not inhibit ovary development. These results confirm that other factors are needed for complete testis development, in particular, those downstream of the SRY protein.  相似文献   

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