1/18. Gonadal tumor and h-y antigen in 46,XY pure gonadal dysgenesis.Six cases of Swyer's syndrome (46,XY pure gonadal dysgenesis) are reported. Three patients, without gonadal tumor, had female h-y antigen. Three patients, after gonadal tumor ablation, had intermediate h-y antigen levels. Repeated blood samples were obtained from two siblings. h-y antigen level in the first sibling, who presented with a gonadoblastoma and underwent a gonadectomy before the H-Y assays, was intermediate, and did not show any significant variation for 21 months. h-y antigen level in the second sibling showed an increase in the male range, presumably due to the presence of gonadoblastomas. After resection of the tumors, h-y antigen level became intermediate. These findings suggest a relation between the tumorization potentiality of the gonadal remnants and the h-y antigen levels in 46,XY pure gonadal dysgenesis.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/18. h-y antigen in a 46,XX female with dysgenetic ovaries.hypogonadism secondary to ovarian dysgenesis or resistant ovary syndrome was diagnosed in a 19-yr-old obese woman with primary amenorrhea, a 46,XX karyotype, and an H-Y cellular phenotype. Small ovoid gonads (1.5 X 0.6 cm) were found found bilaterally; these were encased in a dense venous network. The stroma was ovarian, and primordial follicles and some primary follicles were present, but there were no follicles at or beyond the antrum stage. There was no evidence of testicular tissue and no evidence of malignancy. Analysis of serological data indicated the possibility of residual h-y antigen in the blood cells of the mother.- - - - - - - - - - ranking = 0.5keywords = antigen (Clic here for more details about this article) |
3/18. Mixed gonadal dysgenesis, pathogensis, and management.Fourteen patients with Mixed gonadal dysgenesis who presented as infants or children are discussed. Gonadal asymmetry, and/or sex chromosomal mosaicism, as well as retained mullerian ducts characterize the anomaly. The dysgenetic testis may occur as the result of a cascade of development mishaps stemming from abnormalities of h-y antigen expression or function that lead to abnormal differentiation of the indifferent urogenital ridge and, in turn, to aberrant production of Mullerian inhibiting Substance and testosterone. The latter two cause retention of mullerian ducts and incomplete masculinization of the external genitalia. Absence of a second x chromosome may lead to the formation of a streak ovary, in which the dysgenetic testis may invoke formation of hilar and medullary cords. Neoplastic transformation, so characteristic of this group of patients, may result from unprotected germ cells and abnormally high and prolonged gonadotropin stimulation. gonadoblastoma and seminoma-dysgerminomas are the tumors found in the gonads with the risk exceeding 50% as the third decade is approached. Laterality of the gonads in this anomaly remains an enigma. The gonads should be removed at birth if possible and the external genitalia repaired soon thereafter. These patients should be raised as females. The risk of neoplastic transformations must be considered at all stages of management.- - - - - - - - - - ranking = 0.1keywords = antigen (Clic here for more details about this article) |
4/18. Positive h-y antigen testing in a case of XY gonadal absence syndrome.h-y antigen testing was positive in a case of pseudohermaphroditism due to XY gonadal absence syyndrome. In conclusion, h-y antigen may be present even in the absence of testes. Also, the syndrome could not have originated from a defect in the h-y antigen system.- - - - - - - - - - ranking = 0.7keywords = antigen (Clic here for more details about this article) |
5/18. h-y antigen in Swyer syndrome and the genetics of XY gonadal dysgenesis.The h-y antigen is a plasma membrane antigen involved in the organogenesis of the mammalian testis. Its expression on human cells is determined by a Y-linked gene. Phenotypic females affected by 46,XY gonadal dysgenesis (Swyer's syndrome) can be either H-Y-positive or H-Y-negative. In this paper we report h-y antigen and endocrine studies in a sibship with three affected sisters. Immunological studies were performed on two of the patients, and a clearly positive expression was detected in both cases. Endocrine studies consisted in the investigation of the hypothalamic-pituitary-gonadal axis, which revealed that gonadal hormone insufficiency is the only endocrine abnormality associated with the syndrome. A new genetic interpretation and calssification of XY gonadal dysgenesis is proposed.- - - - - - - - - - ranking = 0.7keywords = antigen (Clic here for more details about this article) |
6/18. Sexual and somatic determinants of the human y chromosome: studies in a 46,XYp- phenotypic female.A case of a 46,XYp- phenotypic female provided an opportunity to evaluate both sexual and somatic determinants for the y chromosome. The patient had multiple stigmata of turner syndrome, but normal stature. laparotomy revealed a normal uterus and tubes, with 1.5 cm undifferentiated gonads. Serological tests for H-Y antigen (ostensibly the product of Y-chromosomal testis-determining genes) indicated absence of the H-Y phenotype normally associated with the intact y chromosome. We conclude that genes exist on the short arm of the human y chromosome which both suppress some of the somatic stigmata of turner syndrome and determine normal expression of h-y antigen and testicular differentiation of the primitive gonad. Our data are consistent with the view that H-Y genes comprise a family of testis-determinants, and that loss of a critical moiety is inconsistent with normal development of the male gonad.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
7/18. h-y antigen expression in a case of mixed gonadal dysgenesis.h-y antigen expression was studied on leukocytes and gonad-derived fibroblasts from a patient affected by mixed gonadal dysgenesis. Blood leukocytes and fibroblasts derived from the testis were typed H-Y positive, but the fibroblasts derived from the streak gonad were H-Y negative. Although the patient's karyotype was a mosaic, 45,XO/46,X mar, as detected in-peripheral blood cells and testis-derived fibroblasts, all the fibroblasts derived from the streak gonad were 45,XO. These data suggests that the marker chromosome was in fact a Y-derived chromosome. Moreover, they showed that, at the gonadal level, a minority of H-Y positive 46,X mar cells were able to organize a testis. Nevertheless, a large number of XO cells probably did not receive the testicular forming influence of the h-y antigen and of the other masculinizing factors.- - - - - - - - - - ranking = 0.6keywords = antigen (Clic here for more details about this article) |
8/18. Absence of h-y antigen in a case of sporadic pure gonadal dysgenesis.H-Y activity, endocrine function and gonadal histology were studied in a phenotypic female presenting with features of sporadic 46,XY pure gonadal dysgenesis. H-Y activity was absent, hormonal data revealed a primary ovarian failure with a blunted response of FSH to LHRH; there was no testicular tissue nor microscopic evidence of gonadal tumor in the gonads. The current view on the role of h-y antigen in the differentiation of the gonads and in the occurrence of gonocytoma is discussed.- - - - - - - - - - ranking = 0.5keywords = antigen (Clic here for more details about this article) |
9/18. Agonadism with positive h-y antigen.A 30-year-old phenotypic female was investigated because of absence of the vagina. Her serum gonadotropins were elevated while testosterone was in the normal range for females. Stimulation with human chorionic gonadotropin (hCG) gave no response of testosterone. No uterus, fallopian tubes, Wolffian derivatives, or the gonads were found at laparotomy. Chromosome analysis showed a 46,XY karyotype. The expression of the h-y antigen was positive. The results suggest that testicular degeneration in agonadism is not caused by a defective h-y antigen.- - - - - - - - - - ranking = 0.6keywords = antigen (Clic here for more details about this article) |
10/18. The X linked recessive form of XY gonadal dysgenesis with a high incidence of gonadal germ cell tumours: clinical and genetic studies.Five phenotypic females in one family had the genotype 46,XY and all had gonadal germ cell tumours. Studies of the family pedigree suggest that this form of XY gonadal dysgenesis is inherited in an X linked recessive manner. G banding of elongated metaphase chromosomes from two subjects with XY gonadal dysgenesis and a female carrier showed no aberrations of the x chromosome. The titres of h-y antigen in three girls with XY gonadal dysgenesis were in the male control range. Thus it appears that, in the X linked form, XY gonadal dysgenesis may be caused by a point deletion or mutation of a gene on the x chromosome, which controls the gonad specific receptor for the h-y antigen. Studies of Xg blood groups were uninformative about linkage of Xg with the X borne gene causing the XY gonadal dysgenesis. Dermatoglyphic studies in the girls with XY gonadal dysgenesis and female carriers revealed high a-b palmar ridge counts and a tendency for the A mainline to terminate in the thenar area. Both of these features have been described in patients with Turner's syndrome.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
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