Dysgenetic Testes Research Articles

Management of müllerian duct remnants

Objectives To describe the presentation and radiologic investigation of 6 patients who had persistent müllerian duct remnants (MDRs) in association with severe hypospadias and to review the long-term results of surgical management using the transtrigonal approach. Methods The hospital records of 6 patients who had MDRs and who underwent transvesical transtrigonal excision were reviewed and long-term assessment of urinary control and continence was made by interview. Results One patient presented in the newborn period with clinically palpable MDRs and five others escaped detection until after the hypospadias repair, despite ultrasonography of the pelvis specifically looking for MDRs. All had undescended testis with severe hypospadias. The karyotype was 45XO/46XY in five and 46XY in one. The most consistently useful examinations were voiding cystourethrography and magnetic resonance imaging. The excision was transtrigonal in each case. Early or late postoperative complications were not encountered in any of our patients. Gonadal histologic examination showed streak gonad in four and a dysgenetic testis in one. Histopathologic examination showed rudimentary uterus and fallopian tubes in 4 patients and a cystic structure lined with squamous and columnar epithelium in 2 patients. No areas of metaplasia were noted. Bladder emptying was normal after surgery. Conclusions Ultrasound examination alone is not always sufficient to diagnose MDRs, which may be responsible for symptoms after hypospadias surgery. The transtrigonal approach provided excellent visualization and access to MDRs and prostatic urethra.

Lack of RBM expression as a marker for carcinoma in situ of prepubertal dysgenetic testis.

Individuals with various intersex states who carry Y-chromosome material bear a high risk of developing testicular neoplasia. In order to gain more insight into the pathogenesis of this neoplasia, the current study evaluates the differentiation of the seminiferous epithelium in 46,XY dysgenetic male pseudohermaphroditism. Immunohistochemical evaluation was performed using the germ cell-specific RNA-binding motif (RBM) protein (encoded by the Y-chromosome) to identify normal germ cells, whereas placental alkaline phosphatase (PLAP) was used to detect neoplastic germ cells. Differentiation of somatic Sertoli cells was assessed using cytokeratin-18 (CK-18) and anti-Müllerian hormone (AMH) as markers for immature Sertoli cells. Specimens were taken from surgically removed dysgenetic gonads of five children (46XY karyotype). Intratubular germ cell neoplasia (carcinoma in situ [CIS] of the testis) was detected in all of them. Normal germ cells revealed immunoreactivity for RBM, whereas the PLAP-positive neoplastic germ cells were negative for RBM expression. Sertoli cells revealed an immature phenotype indicated by AMH expression in their cytoplasm. The design of the current study is unique in its assessment of the state of germ cell differentiation in dysgenetic gonads by the use of the RBM protein, which was expressed only in normal germ cells but not in those of CIS. Testicular dysgenesis interrupted the normal differentiation of the germ line and had no effect on the immature phenotype of the prepubertal Sertoli cells. This points toward the germinal component of CIS as the precursor for the promotion of testis cancer.

Testicular pathology in 46,XY dysgenetic male pseudohermaphroditism: an approach to pathogenesis of testis cancer.

Eleven children with dysgenic male pseudohermaphroditism (DMP) and 18 boys with isolated penile hypospadias, all with 46,XY karyotype, were studied. Testicular dysgenesis was associated with significantly lower testosterone response to human chorionic gonadotropin (0.9 +/- 0.2 ng/mL) than it was in hypospadias (3.3 +/- 0.1 ng/mL), and with significantly higher mean serum follicle-stimulating hormone (FSH) levels (8.4 +/- 2.3 IU/L vs 1.5 +/- 0.3 IU/L). Gonadoblastoma, a tumor that arises from the sex cords, was found in more than 1/4 of patients with DMP, whereas testicular carcinoma in situ (CIS) cells were present in all of these patients. Forty-two percent to 98% of CIS cells revealed an aneuploid pattern of nuclear DNA, indicating that most of them are neoplastic cells. In patients with hypospadias, CIS was not seen, and no other abnormalities were detected. In children with DMP, the percentage of tubules populated with germ cells was significantly lower than it was in those with hypospadias (48.3% +/- 10.6% vs 92.4% +/- 4.0%). The total number of germ cells (CIS cells + spermatogonia) did not differ significantly between the 2 groups, but the number of spermatogonia was significantly reduced in children with DMP (0.08 +/- 0.05 vs 3.65 +/- 0.2), suggesting impaired differentiation of gonocytes to spermatogonia. The following significant correlations were present with DMP: 1) the higher the seminiferous tubule cross-section area, the higher the number of CIS cells (r = 0.78); and 2) the higher the serum gonadotropin levels, the higher were tubular diameter (r = 0.93 for FSH and r = 0.75 for luteinizing hormone [LH]), area (r = 0.79 for FSH and r = 0.82 for LH), percentage of tubules populated with germ cells (r = 0.86 for FSH and r = 0.81 for LH), and number of CIS cells (r = 0.87 for FSH and r = 0.79 for LH). The results indicate that in intersex children with 46,XY karyotype, CIS occurs in dysgenetic testes in all cases and is frequently associated with gonadoblastoma. Impaired organogenesis of sex cords, relative inhibition of testosterone secretion, and the associated increased secretion of gonadotropins may create a milieu that induces or is favorable for the formation or maintenance of neoplastic lesions in dysgenetic testes early in childhood.

Estrogen-induced gonadal sex reversal in the tammar wallaby.

Estrogens have a feminizing effect on gonadal differentiation in fish, amphibians, reptiles, and birds. However, the role of estrogen during gonadal differentiation in mammals is less clear. We investigated the effect of estrogen on gonadal differentiation of male tammar wallabies. Male pouch young were treated orally with estradiol benzoate or oil from the day of birth, before seminiferous cords develop, to Day 25 postpartum and were killed at Day 50 postpartum. In all estrogen-treated neonates, a decrease in gonadal volume, volume of the seminiferous cords, thickness of the tunica albuginea, and number of germ cells was found. The stage of treatment affected the magnitude of the response. Two of three male young born prematurely after 25 days of gestation and treated subsequently with estradiol had ovary-like gonads, with well-developed cortical and medullary regions and primordial follicle formation. Furthermore, at Day 50 postpartum, many (21%) of the germ cells in these sex-reversed ovaries were in the leptotene and zygotene stages of meiosis, similar to female germ cells at the same stage of development. In the other males born on Day 26 of gestation or later, estradiol treatment from the day of birth caused development of dysgenetic testes, with abnormal Sertoli cells, atrophy of the seminiferous tubules and tunica albuginea, and absence of meiotic germ cells. In this marsupial, therefore, estradiol can induce either partial or complete transformation of the male gonads into an ovary with meiotic germ cells. These results confirm that estrogen can inhibit early testicular development, and that testis determination occurs during a narrow window of time.

Molecular analysis of SRY gene in patients with mixed gonadal dysgenesis

Mixed gonadal dysgenesis (MGD) includes a group of heterogeneous conditions consisting of a dysgenetic testis with a streak gonad. MGD is probably due to a disturbance in testicular determination/differentiation. The objective of this study is to analyze the SRY gene in MGD patients. A molecular investigation was undertaken in sixteen patients with this disorder in an attempt to determine mutations in SRY through polymerase chain reaction, single strand conformational polymorphism and direct sequencing. Eleven patients showed 45,X/46,XY and five 46,XY karyotype. Mutations in SRY gene were shown to be absent in these patients. This study confirms the findings of other studies. The etiology of MGD is heterogeneous, and cytogenetics mosaicism typically seen in these patients may be a cause of this condition, although, the presence of mutations in testicular organizing genes downstream of SRY is still to rule out.

45,X/46,XY mosaicism: report of 27 cases.

There exist substantial differences between prenatally and postnatally diagnosed cases of 45,X/46,XY mosaicism. Ninety percent of prenatally diagnosed cases show a normal male phenotype, whereas the postnatally diagnosed cases show a wide spectrum of phenotypes. This 10% risk of an abnormal outcome in prenatally diagnosed cases requires further attention. The purpose of the present study is to provide more information on the postnatally diagnosed 45,X/46,XY mosaicism cases. To date, only a few series have been reported. An accurate diagnosis in these patients is essential not only to their follow-up, but also to providing appropriate genetic counselling and subsequent prenatal diagnosis to their parents. The clinical, cytogenetic, endocrinologic, histologic and molecular biological findings of 27 patients with 45, X/46,XY mosaicism are analyzed. The reported cases showed a wide spectrum of phenotypes as Turner syndrome, mixed gonadal dysgenesis (MGD), male pseudohermaphroditism (MPH) and apparently normal male. However, Ulrich-Turner stigmata were the most common features found in this series. Patients with MGD or MPH presented with various degrees of sex reversal such as hypospadias and/or abnormal internal genitalia. No correlation between the proportion of the 45,X/46,XY cell lines in the blood or the fibroblasts and the phenotype was found. Mild mental retardation was present in 4 of the patients and 2 patients showed signs of autism. Two major points are emphasized in this series: 1) the presence in 7 histologically analyzed streak gonads of a homogeneous 45,X chromosomal complement suggests that the invasion of the primitive genital ridge by a such a cell line may induce abnormal gonadal development; 2) 3 males, apparently normal at birth, developed late onset abnormalities such as dysgenetic testes leading to infertility, Ulrich-Turner stigmata, dysmorphic features, and mild mental retardation. These data indicate the importance of an accurate clinical and histologic evaluation of any patient presenting with 45, X/46,XY mosaicism.

Molecular analysis of SRY gene in patients with mixed gonadal dysgenesis

Mixed gonadal dysgenesis (MGD) encompasses a group of heterogeneous conditions consisting in presence of a dysgenetic testis with a streak gonad. MGD is probably due to an disturb in the determination/ differentiation testicular. The purpose of this study is to analyze SRY gene in MGD patients. A molecular investigation was undertaken in fifteen patients with disorder in an attempt to determine mutations in SRY through polymerase chain reaction, single strand conformational polymorphism and direct sequencing. Ten patients showed 45,X/46,XY and five 46,XY karyotype. Mutations in SRY gene were shown to be absent in 45,X/46,XY and 46,XY patients. This study confirm the findings of other studies. The primary etiology of MGD is heterogeneous, and cyotogenetic mosaicism typically seen in these patients may be a cause of this condition, although the presence of muations in testicular organizing genes downstream of SRY is still to rule out.

Aniridia, Gonadoblastoma, Wilms' Tumor and Deletion 11p13

An incidence of bilateral gonadoblastoma in a 23-month old, mentally retarded boy with congenital sporadic aniridia, undescended dysgenetic testes, deletion of a chromosome (11) (p1302p14.2) and a later occurring unilateral Wilms' tumor is reported. The patient was treated by bilateral gonadectomy, nephrectomy, and chemotherapy, and is alive and well five years later. Another three aniridia/gonablastoma observations from the literature are discussed, two of them without and one in combination with Wilms' tumor. Diagnosis of gonadoblastoma remained unsuspected in two cases until autopsy and in another two cases it was done at surgery. A comparison of four cases reveals common finding--aniridia, dysgenetic gonads, genital abnormalities, mental retardation, deletion of 11p13, early occurrence and bilaterality of gonadoblastoma.

Mullerian inhibiting substance in humans: normal levels from infancy to adulthood.

Mullerian-inhibiting substance (MIS) is a gonadal hormone synthesized by Sertoli cells of the testis and granulosa cells of the ovary. To facilitate the use of MIS for the evaluation of intersex disorders and as a tumor marker in women with MIS-expressing ovarian tumors, we measured MIS in 600 serum samples from males and females. These data show that mean MIS values for males rise rapidly during the first year of life and are highest during late infancy, then gradually decline until puberty. In contrast, MIS values in females are lowest at birth and exhibit a minimal increase throughout the prepubertal years. Whereas MIS is uniformly measurable in all prepubertal boys studied, it is undetectable in most prepubertal female subjects. These data reveal an easily discernible sexually dimorphic pattern of expression and confirm that MIS can be used as a testis-specific marker during infancy and early childhood. MIS values that are above the upper limits for females are discriminatory for the presence of testicular tissue or ovarian tumor, and those below the lower limits for males are consistent with dysgenetic or absent testes or the presence of ovarian tissue. These data will enable normal and abnormal levels of MIS to be differentiated with higher precision and will facilitate the use of MIS in the management of gonadal disorders.

Testicular dysgenesis and mental retardation in two siblings with male pseudohermaphroditism

Two mentally disabled phenotypic females, 46,XY dysgonadal sisters from a consanguineous marriage are described. Low plasma testosterone levels and an inadequate response of plasma-testosterone to human chorionic gonadotrophin (hCG) stimulation were noted in both cases. Dysgenetic testes and remnants of the müllerian and wolffian ducts were identified at exploratory laparotomy. Mild mental retardation was also present in both cases. These data may suggest the specific role of genetic factors in the etiology of testicular dysgenesis.

Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism--a critical analysis.

A 10 year prospective study of 14 patients with mixed gonadal dysgenesis (MGD) and six patients with dysgenetic male pseudohermaphroditism (DMP) is reported. All of them had internal mullerian structures, along with unilateral or bilateral dysgenetic testes, ambiguous external genitalia. Twelve had been brought up as male, nine of whom had a unilateral descended testis. Eight had been reared as females, as they had bilaterally undescended gonads, and ambiguous genitalia. Clinical examination, retrograde genito-urethrography and cytogenetic studies suggested the diagnosis in 16 patients, while four were diagnosed on inguino-abdominal exploration for undescended testis. This report delineates more clearly the clinical profile of these orders. All the patients reared as male were assigned the male gender following abdominal gonadectomy, retention of scrotal testis and male genitoplasty. The eight patients who were reared as females underwent bilateral salpingo-gonadectomy and female genitoplasty. This management differs from the usual recommendation that all such children should be reared as females. Ten patients (50%) had maternal history of previous abortion/stillbirth, or drug intake in the first trimester of pregnancy suggesting a role of these factors in the etiology. All cases of DMP had a 46,XY karyotype, while eight of 14 cases of MGD had mosaicism with 45X/46,XY cell lines in blood or gonadal cultures. The clinicopathological features of patients of MGD and DMP were similar. It is suggested that these two disorders represent different spectra of the same disorder. A unifying concept of etiopathogenesis is proposed.

Clinical and Pathologic Spectrum of 46,XY Gonadal Dysgenesis

The condition termed "46,XY gonadal dysgenesis" is characterized by a 46,XY karyotype and incomplete testicular determination. It is likely the result of a mutation in the gene for the testicular determination factor or in another gene involved in the early stages of testicular differentiation. In view of the present interest in the identification of gene(s) initiating the differentiation of the embryonic gonads into testes, we have reviewed the phenotype of 15 patients with 46,XY gonadal dysgenesis to use this information for future molecular studies. Seven patients presented a complete form, 46,XY pure gonadal dysgenesis, including streak gonads, normal Müllerian structures, and normal female external genitalia. The structure of the streak gonads in these patients presented some variation. Eight patients presented an incomplete form, 46,XY partial gonadal dysgenesis, with ambiguous external genitalia and partial development of Müllerian and Wolffian structures. Among them, 3 had bilateral dysgenetic testes, and 4 had a streak gonad on one side with a contralateral dysgenetic testis. The streak gonads showed ovarian stroma with occasional primitive sex cords devoid of germ cells. However, a primordial follicle was observed in 1 streak gonad. The dysgenetic testes showed disorganized seminiferous tubules and ovarian stroma. In some patients, the ovarian stroma was intermixed with testicular tissue, while in others, distinct ovarian and testicular portions were present. In 1 patient, the dysgenetic testis contained a focus of well-differentiated ovarian tissue with primordial follicles. Our observations support the hypothesis that streak gonads in 46,XY pure gonadal dysgenesis arise from fetal ovaries and that dysgenetic testes in the partial form in 46,XY partial gonadal dysgenesis develop from ovotestis.(ABSTRACT TRUNCATED AT 250 WORDS)

Testicular Dysgenesis and Mental Retardation in Two Incompletely Masculinized XY-Siblings

Aberrations of fetal sexual development were studied in two retarded phenotypic female 46,XY dysgonadal sisters from a consanguineous marriage. Endocrine evaluation revealed an inadequate response of plasma-testosterone to human chorionic gonadotropin (hCG) stimulation and a normal response to adrenocorticotropic hormone (ACTH) administration. At exploratory laparotomy dysgenetic testes and remnants of the Müllerian and of the Wolffian duct were found. Loss of testicular function, resulting in male pseudohermaphroditism (MPH), can occur at different times during intrauterine development, resulting in a variety of clinical manifestations. A thorough evaluation is warranted in all patients in order to reach a correct diagnosis which is of importance for appropriate gender assignment and genetic counseling.

性染色体モザイク症の臨床的検討

In order to clarify the clinical aspects of sex chromosomal mosaicism, we evaluated the karyotypes, the anatomy of external genitalia and internal ductal system, the pituitary-gonadal function, and the histopathology of the gonads by immuno-staining for glutathion S-transferase (GST) in 5 patients who had been all raised as female. Three patients have the 45, X/46, XYq- karyotype in the initial lymphocyte culture or the subsequent culture of skin fibroblasts. Another two karyotypes were 45, X/46, XYq-/47, XYq-, Yq- and 45, X/46, XdicY. Thus, Y chromosome of all patients retained short arms in which the testis determining factor is encoded. Three prepubertal patients were referred to us for their ambigious external genitalia and two postpubertal patients were for the short statures. Although the vaginal orifice was separated from the urethral meatus in all of them, the phallic enlargement was noted in 4 patients and the posterior labial fusion in 2 patients. The oldest patient had a normal female appearance of external genitalia except the vaginal septum. Serum gonadotrophin (GnH) levels were basically high in the postopubertal patients and the responses of GnH to LH-RH were significantly increased in the prepubertal patients. Serum testosterone levels to hCG stimulation ranged from no response to low normal response. All patients underwent the exploratory laparotomy together with the feminizing genitoplasty. The gonads in 3 patients, diagnosed as mixed gonadal dysgenesis (MGD), consisted of a unilateral testis and a contralateral streak gonad. Two patients had variants, including one with bilateral dysgenetic testis and another with bilateral streak gonads.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on gonadal dysgenesis: variable expressivity of the XY testicular dysgenesis syndrome; two case reports

Two adult unrelated XY phenotypically female individuals with sexual infantilism and genital ambiguity were studied. Mosaicism was ruled out by the assessment of a normal 46,XY karyotype in four different cell lines. Persistently elevated LH and FSH serum levels with concomitant normal pituitary Gn-RH responsiveness were found. Baseline serum testosterone concentrations were low, but they exhibited a slight though significant rise following HCG stimulation. Surgical and histological findings included the presence of Mullerian and Wolffian derivatives and small bilateral dysgenetic testes with absence of germ cell epithelium, scarce Sertoli cells, and hyperplastic Leydig cells. The overall data indicated an anatomofunctional testicular impairment particularly confined to the tubular compartment. By comparing the clinical and endocrine features of this incomplete form of the XY testicular dysgenesis with the complete and other unusual forms, further evidence is provided of a wide heterogeneity of the syndrome, and a more detailed classification is proposed.

The Y-chromosomal and autosomal testis-determining genes

ABSTRACT It has been conclusively shown that a majority of XX males has acquired Y-chromosome-specific DNA (Y-DNA) sequences from their father’s Y chromosome. Testicular differentiation in these XX males is very likely induced by the testis-determining factor, TDF, normally located on Yp. The phenotypic expression of TDF in the presence of two X chromosomes is a male habitus, dysgenetic scrotal testes and no ambiguity of the genitalia. Among those XX males who do not have Y-DNA detectable by presently used methods, some, but not all have ambiguity of the genitalia with or without hypospadias. XX true hermaphrodites are characterized by the presence of both testicular and ovarian tissue and have ambiguous genitalia. They do not have Y-DNA. Several instances of familial XX maleness are critically analysed. In these pedigrees, most of the affected individuals are true hermaphrodites or XX males with ambiguous genitalia; in at least one family no Y-DNA occurred in these individuals. Typical autosomal dominant inheritance of XX testicular differentiation occurs in informative pedigrees. The suggested conclusion is that an autosomal dominant testis-determining factor, TDFA, exists. TDFA shows somewhat variable expression in XX individuals often causing genital ambiguity or true hermaphrodism. TDFA has no phenotypic effect on XY individuals. It is argued that XX males without presently detectable Y-DNA are caused either by TDF or TDFA.

The Association of Wilms' Tumor, Male Pseudohermaphroditism and Diffuse Glomerular Disease (Drash Syndrome)

In 8 children (6 males) at least 2 of 3 disorders were found--male pseudohermaphroditism (MPH), Wilm's tumor, and glomerular disease. MPH was present in the 6 males; they had abdominal cryptorchidism (6/6), ambiguous genitalia (6/6), negative sex chromatin (5/5), and 46XY karyotype (2/2). The gonads examined microscopically in 3 patients were dysgenetic testes. The renal tumor present in 7 was nephroblastoma (NB) of the classical type without anaplasia or nephroblastomatosis, bilateral in 1, and unilateral but multinodular in 2. Five underwent nephrectomy for a renal mass, and in 2 NB was found at open biopsy or at autopsy. The mean age at diagnosis was 10 months. Glomerular disease in 6 patients began with onset of the nephrotic syndrome between 20 days and 39 months of age; it was resistant to steroid therapy and led to death from renal failure. Microscopically the glomerular process was a diffuse mesangial sclerosis (DMS). The 2 children with NB and MPH, but without DMS are healthy 2 1/2 and 9 years postnephrectomy. Neither familial incidence nor parental consanguinity was found. This syndrome has complete and partial forms, and its early recognition is important both for patient management and for assessment of prognosis.

Unilaterally impalpable testis.

Thirty children presenting with a unilateral impalpable testis and a normally descended contralateral testis underwent surgical exploration. The testis was absent ('vanishing testis') in 12 cases (40%) and orchidectomy for a dysgenetic testis was performed in a further 5 cases. The overall rate of monorchism following surgery was therefore 56%. It is desirable that parents be advised of this possibility pre-operatively.

163 ABNORMAL Y CHROMDSOME IN 45, X/46,XY MOSAICISM

The mosaicism 45,X/46,XY is one of the sex chromosome abnormalities with a wide phenotypic expression. In 23 cases of XO/XY mosaicism diagnosticated by us, the phenotypic manifestations vary from phenotypic females with clinical Turner's syndrome and bilateral streaks (2 cases) to phenotypic male with infertility disorder (1 case), being the asymmetrical gonadal differentiation with ambiguous external genitalia (15 cases) and males with hypospadias and bilateral normal or dysgenetic testes (5 cases) the most frequent expressions. The use of chromosome banding techniques, mainly Q and C ban ds, allowed to find an unexpectedly high proportion of abnormal-Y chromosome in XO/XY mosaicism, suggestiong that such altered Y chromosome may predispose to anaphase lag or to mitotic non-disjunction leading to XO/XY or XO/XY/XYY mosaicism, respectively. From own 10 cases re-studied with chromosome bands techniques, five of them (50 %) presented an abnormal Y chromosome: 3-Ygh- and 2-idic (Yq). The three patients with the Y chromosome without the heterocromatic region, studied with high resolution chromosome methodology, showed to be an isodicentric for the short arm of Y chromosome: idic (Yp). We suggest that the origin of the mosaicism XO/XY could be due to an abnormal and unstable Y chromosome such as an isodic. Yp.

HY INTERMEDIATE PHENOTYPE: A POSSIBLE CAUSE OF TESTICULAR DYSGENESIS

The HY antigen is closely associated with the presence of testicular tissue which is thought to be induced during embryogenesis by the interaction of HY and its receptor. In coded samples, we examined the HY antigen in peripheral lymphocytes from a patient with male pseudohermaphroditism and dysgenetic testes whose karyotype in lymphocytes and gonadal fibroblasts was 46 XY. Results are as follows (mean + SD): The patient's lymphocytes exhibited an HY phenotype intermediate between that of the normal male and normal female and between that of the patient's mother and father. These results indicate a correlation between HY phenotype and abnormal testicular development and suggests the possibility that a partial deficiency of HY may have been responsible for the testicular dysgenesis in this patient.