RESUMEN
PURPOSE: We surveyed a clinic sample of adult 46,XY intersex patients regarding attitudes to clinical management policies. MATERIALS AND METHODS: All adult former patients of 1 pediatric endocrine clinic in the eastern United States whose addresses could be obtained and who consented to participation were surveyed by a comprehensive written followup questionnaire. Three questions on attitudes concerning the desirability of a third gender category and the age at which genital surgery should be done were presented in the context of ratings of satisfaction with gender, genital status and sexual functioning. RESULTS: A total of 72 English speaking patients with 46,XY, including 32 men and 40 women 18 to 60 years old, completed the questionnaire. The majority of respondents stated that they were mainly satisfied with being the assigned gender, did not have a time in life when they felt unsure about gender, did not agree to a third gender policy, did not think that the genitals looked unusual (although the majority of men rated their penis as too small), were somewhat or mainly satisfied with sexual functioning, did not agree that corrective genital surgery should be postponed to adulthood and stated that their genital surgeries should have been performed before adulthood, although there were some significant and important differences among subgroups. CONCLUSIONS: The majority of adult patients with intersexuality appeared to be satisfied with gender and genital status, and did not support major changes in the prevailing policy. However, a significant minority was dissatisfied and endorsed policy changes.
Asunto(s)
Actitud , Trastornos del Desarrollo Sexual/psicología , Adolescente , Adulto , Trastornos del Desarrollo Sexual/terapia , Femenino , Estudios de Seguimiento , Identidad de Género , Humanos , Masculino , Persona de Mediana Edad , Encuestas y CuestionariosRESUMEN
In the absence of long-term results of experimental therapies, a common sense approach toward dealing with the growth of patients who have CAH is desirable. First, an effort can be made to decrease the replacement cortisol dose during the first year of life. Doubling, rather than tripling, the basal dose at times of stress could be helpful. The use of adjunctive therapy for infections could result in fewer fevers. After 1 year of age, mean parental height could be used to establish at which centile the child should theoretically grow. The dose of cortisol could be adjusted to maintain the bone age between +/- 1 SD. Plasma androstenedione levels should not rise above 50 ng/dL, and 17-hydroxyprogesterone should not be totally suppressed but be maintained between 500 and 1000 ng/dL. Compliance with therapy should be encouraged, particularly for adolescent patients. In the final analysis, a realistic expectation for patients would be a height between the 50th and third percentile of the normal growth curve and, in some cases, slightly below the third percentile when the genetic potential is slight.
Asunto(s)
Hiperplasia Suprarrenal Congénita , Hiperplasia Suprarrenal Congénita/fisiopatología , Hiperplasia Suprarrenal Congénita/terapia , Hiperplasia Suprarrenal Congénita/enzimología , Adrenalectomía , Estatura , Femenino , Enfermedades Fetales/tratamiento farmacológico , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Terapia de Reemplazo de Hormonas , Humanos , Masculino , Mineralocorticoides/administración & dosificación , Mineralocorticoides/uso terapéutico , EmbarazoRESUMEN
OBJECTIVES: To document long-term medical, surgical and psychosexual outcome of individuals with congenital micropenis (13 males, 5 females). METHODS: Physical measurements from childhood were collected retrospectively from medical records and at adulthood by physical examination. An adult psychosexual assessment was conducted with a written questionnaire and oral discussion. RESULTS: Adult penile length was below the normal mean in all men. Three women had vaginoplasty resulting in normal length. All men reported good or fair erections but 50% were dissatisfied with their genitalia. Dissatisfaction with body image resulted from having a small penis (66%), inadequate body hair (50%), gynecomastia (33%) and youthful appearance (33%). Ten men were heterosexual, 1 homosexual and 2 bisexual. Among women, 4 (80%) were dissatisfied with their genitalia. Three women reported average libido with orgasm and were also heterosexual. Two women had no sexual interest or experience. Finally, males were masculine and females feminine in their gender-role identity, and both groups were satisfied with their sex of rearing. CONCLUSIONS: Regarding choice of gender, male sex of rearing can result in satisfactory genito-sexual function. Female gender can also result in success, however it requires extensive feminizing surgery.
Asunto(s)
Pene/anomalías , Desarrollo Psicosexual , Adolescente , Imagen Corporal , Niño , Preescolar , Anomalías Congénitas/fisiopatología , Anomalías Congénitas/psicología , Anomalías Congénitas/cirugía , Anomalías Congénitas/terapia , Consejo , Femenino , Estudios de Seguimiento , Genitales Femeninos/fisiopatología , Genitales Masculinos/fisiopatología , Humanos , Lactante , Masculino , Matrimonio , Satisfacción del Paciente , Pene/patología , Sexo , Conducta SexualRESUMEN
Over the past decade, knowledge of the genetic control of human sex differentiation has greatly expanded our understanding of the developmental processes needed to form a male or female. The purpose of this review is to discuss how transcription factors are relevant to such processes. Additionally, an attempt is made to relate current knowledge of these factors with gender development of subjects with intersex conditions. Finally, we discuss how information about the genetic control of sex differentiation may contribute to decisions about medical treatment of individuals with conditions of abnormal sex differentiation.
Asunto(s)
Diferenciación Sexual/genética , Diferenciación Sexual/fisiología , Factores de Transcripción/genética , Animales , Femenino , Humanos , Masculino , Caracteres SexualesRESUMEN
Controversy concerning the most appropriate treatment guidelines for intersex children currently exists. This is due to a lack of long-term information regarding medical, surgical, and psychosexual outcome in affected adults. We have assessed by questionnaire and medical examination the physical and psychosexual status of 14 women with documented complete androgen insensitivity syndrome (CAIS). We have also determined participant knowledge of CAIS as well as opinion of medical and surgical treatment. As a whole, secondary sexual development of these women was satisfactory, as judged by both participants and physicians. In general, most women were satisfied with their psychosexual development and sexual function. Factors reported to contribute to dissatisfaction were sexual abuse in one case and marked obesity in another. All of the women who participated were satisfied with having been raised as females, and none desired a gender reassignment. Although not perfect, the medical, surgical, and psychosexual outcomes for women with CAIS were satisfactory; however, specific ways for improving long-term treatment of this population were identified.
Asunto(s)
Síndrome de Resistencia Androgénica/fisiopatología , Síndrome de Resistencia Androgénica/psicología , Desarrollo Psicosexual , Sexualidad , Adulto , Anciano , Síndrome de Resistencia Androgénica/cirugía , Población Negra , Estatura , Imagen Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducta Sexual , Encuestas y Cuestionarios , Estados Unidos , Población BlancaRESUMEN
During the 10-year period from 1979 to 1988 we evaluated 60 boys who were more than 9 years old and who had significant breast development (greater than 4 cm in diameter) around the time of puberty. An endocrine abnormality was identified in seven subjects. The pathology included Klinefelter's syndrome; 46,XX maleness; primary testicular failure; partial androgen insensitivity; fibrolamellar hepatocarcinoma; and increased aromatase activity. Eight of the remaining 53 subjects had underlying medical problems, five of them having neurologic disorders. The 45 remaining subjects were considered to have significant idiopathic gynecomastia, a condition sometimes referred to as macromastia. These boys tended to be both taller and heavier than average, the mean Z score for height being 1.4 SDs above the mean and the mean weight score being 2.7 SDs above the mean. This study underscores the observation that pathologic causes of marked pubertal gynecomastia are unusual. However, the potential for significant health problems among boys with marked breast development supports the need for an endocrine evaluation of all affected subjects. Our data also indicate that boys with marked idiopathic breast development have greater body mass than other boys of similar age. This may contribute in part to the greater breast development in these subjects.
Asunto(s)
Ginecomastia/etiología , Síndrome de Klinefelter/complicaciones , Pubertad , Estatura , Índice de Masa Corporal , Peso Corporal , Niño , Ginecomastia/genética , Humanos , Cariotipificación , Síndrome de Klinefelter/genética , Masculino , Aberraciones Cromosómicas SexualesRESUMEN
A person's sex can be considered across various levels. To illustrate, genes, hormones, and genitalia can all be considered physical markers of a person's sex. In addition to physical markers, behaviors such as gender role, gender identity and sexual orientation can be perceived as stereotypically male or female. The purpose of this review is to summarize current knowledge of sexual differentiation which emphasizes genetic and hormonal mechanisms that result in male and female development of gonads and genitalia. Finally, consideration is given to associations between genetic sex, gonadal sex, and hormonal sex with gender.
Asunto(s)
Diferenciación Sexual/genética , Diferenciación Sexual/fisiología , Animales , Femenino , Gónadas/fisiología , Hormonas/fisiología , Humanos , Masculino , Fenotipo , Caracteres SexualesRESUMEN
We have reported a kindred in which 46,XY gonadal dysgenesis was inherited in an X-linked (or autosomal dominant sex-limited) manner and in which affected subjects did not have a large duplication of the short arm of the X-chromosome. In the present study we used linkage and sequence analyses to test the role of X-linked and various autosomal genes in the etiology of the familial 46,XY partial gonadal dysgenesis. For analysis of X-linkage, 28 microsatellite polymorphisms and 1 restriction fragment length polymorphism were studied. The genotypes of informative family members were determined at each locus, and data were analyzed. Despite the large number of loci tested, our studies did not establish linkage between the trait and an X-chromosomal locus. With respect to the study of autosomal genes, linkage analysis using a polymorphism within the 3'-untranslated region of the WT1 gene excluded involvement of WT-1 in the etiology of the abnormal gonadal differentiation of the family in this study. Similarly, linkage analysis using four microsatellites on the distal short arm of chromosome 9 was not consistent with linkage. Linkage analysis of a locus close to the SOX9 gene as well as analysis of the coding region of the SOX9 gene suggested that this gene was not associated with the trait in the affected subjects we studied. Our data suggest the role of an autosomal gene in the abnormal gonadal differentiation in the family in the study, but do not formally exclude the role of an X-chromosome gene.
Asunto(s)
Ligamiento Genético , Disgenesia Gonadal 46 XY/genética , Mapeo Cromosómico , Proteínas de Unión al ADN/genética , Femenino , Proteínas del Grupo de Alta Movilidad/genética , Humanos , Masculino , Factor de Transcripción SOX9 , Factores de Transcripción/genética , Proteínas WT1 , Cromosoma XRESUMEN
Among a group of patients with abnormal sexual differentiation, we have identified two subjects who had a 46,XY karyotype, ambiguous genitalia, and well-developed Müllerian structures, but normal appearing testes. The presence of ambiguous genitalia and persistent Müllerian structures implied both Leydig cell and Sertoli cell dysfunction, hence, gonadal dysgenesis. However, the normal testicular histology suggested that the underlying abnormality was not a defect in testis determination itself but an abnormality in timing of gonadal ridge and testis development. In one of the two subjects genomic DNA was available. The sequence of the SRY gene was normal. Because rare patients with partial androgen insensitivity may have a similar phenotype, the AR gene was evaluated by denaturing gradient gel electrophoresis (DGGE) and was normal. Some subjects with mutation of the WT1 gene or with deletion of the distal short arm of chromosome 9 may have similar phenotypes. The WT1 gene was studied by single-strand conformation polymorphism (SSCP) analysis and was normal. In addition, there was no loss of heterozygosity of polymorphic markers in distal 9p. The gene for Müllerian inhibiting substance (MIS) was also studied by SSCP and was normal. Although the exact mechanism for the defect in the two subjects is unknown, it may be due to an abnormality in a gene or genes involved in the timing of gonadal ridge development.
Asunto(s)
Diferenciación Celular , Disgenesia Gonadal/genética , Gónadas/anomalías , Conductos Paramesonéfricos/anomalías , Testículo/crecimiento & desarrollo , Humanos , Recién Nacido , Masculino , Fenotipo , Reacción en Cadena de la PolimerasaRESUMEN
The HLA-B47,DR7 haplotype in congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency contains a deletion of most of the active CYP21 gene and the entire adjacent C4B gene. The C4A gene produces a protein which is electrophoretically C4A but antigenically C4B. In the Old Order Amish, the HLA-B47,DR7 haplotype contains no deletion, but is immunologically identical to the CAH haplotype in both areas flanking the crossover region. We compared some of the genes in the MHC Class II and Class III regions in the Amish and CAH-linked haplotypes to define further the relationships between the two. The complement factor B (Bf) proteins differed, but no Bf RFLPs were identified. The complement factor 2 genes exhibited different BamHI RFLPs. Analyses of the tumor necrosis factor-alpha genes revealed the same NcoI restriction patterns. The RD genes contained microsatellites of the same size. Portions of the MHC Class II DR and DQ, and Class III CYP21 and C4 alleles were sequenced. The exon 2 sequences of DQ2 and DR7 were identical in the two haplotypes. In the Amish haplotype, both CYP21 and C4 gene pairs were present and functionally normal. The CAH haplotype had two sequence crossovers: from CYP21P to CYP21 in the 7th intron, and from C4A to C4B between codons 1106 (exon 26) and 1157 (exon 28). A model is proposed which accounts for the CAH-linked mutant haplotype arising from a nonmutant homologue via three crossings-over.
Asunto(s)
Hiperplasia Suprarrenal Congénita , Intercambio Genético/inmunología , Etnicidad/genética , Haplotipos/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Esteroide 21-Hidroxilasa/genética , Secuencia de Bases , Niño , Complemento C4/genética , Factor B del Complemento/genética , ADN Satélite/genética , Antígeno HLA-A3/genética , Antígenos HLA-C/genética , Antígeno HLA-DR7/genética , Humanos , Datos de Secuencia Molecular , Esteroide 21-Hidroxilasa/inmunología , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Determination of the plasma concentration of testosterone (T) is important in evaluating infants born with ambiguous genitalia and micropenis, and several commercially available kits provide a direct assay of T in unextracted plasma. Using plasma samples obtained from 36 subjects < 6 months old, we compared the concentration of plasma T measured by RIA after extraction and purification by column chromatography with the T concentration measured in a direct assay. When aliquots of samples were purified before RIA, the concentration of T was markedly lower than in the direct assay. In the first 3 weeks postpartum, results of the direct assay were 3.8-fold greater than those obtained after purification. This difference decreased over time, and by age 2 months there was fairly good agreement between the two methods. These data indicate that some direct assays of plasma T are inappropriate during the first 2 months postpartum.
Asunto(s)
Cromatografía , Trastornos del Desarrollo Sexual/sangre , Testosterona/sangre , Tetracloruro de Carbono , Femenino , Identidad de Género , Humanos , Lactante , Recién Nacido , Masculino , RadioinmunoensayoRESUMEN
Mutations of the human androgen receptor gene were identified in five subjects from four families with androgen insensitivity syndrome. Individual exons of the androgen receptor gene were amplified by the polymerase chain reaction from genomic DNA and screened for sequence-dependent differences in their melting characteristics by denaturing gradient gel electrophoresis. DNA fragments from exons with altered mobility were sequenced. Four different single nucleotide base substitutions were found within exons 5, 6, and 7 encoding the steroid-binding domain of the androgen receptor. In one subject with ambiguous genitalia, amino acid residue 763 was changed from tyrosine to cysteine (TAC-->TGC; Y763C). Four subjects, including two siblings, had complete androgen insensitivity. In one subject, residue 779 was changed from arginine to tryptophan (CGC-->TGG; R779W), another subject (M807V) had a substitution of valine (GTG) for methionine (ATG) residue at position 807, and the two siblings (R855C) had a mutation in residue 855 changing arginine (CGC) to cysteine (TGC). Binding of the synthetic androgen ligand, methyltrienolone (R1881), by the mutant receptor Y763C was decreased by 54% compared to the normal receptor. Transcriptional activation of a mouse mammary tumor virus-chloramphenicol acetyltransferase (MMTV-CAT) reporter gene by AR mutant Y763C was negligible at 0.1 nM R1881 and only 55% at 10 nM R1881 when compared to the maximal response with the normal AR, as assessed by CAT activity. Mutant M807V retained only 22% of normal R1881 binding and mutant R855C was unable to bind the steroid. In accordance with the steroid binding, transcriptional activation of MMTV-CAT by M807V rose to only 26% of control in the presence of 10 nM R1881, a concentration at which R855C remained functionally inactive. In summary, missense mutations within the exons of the androgen receptor gene encoding the steroid-binding domain of the receptor are common causes of both partial and complete forms of androgen insensitivity syndrome.
Asunto(s)
Síndrome de Resistencia Androgénica/genética , Andrógenos/fisiología , Mutación Puntual , Receptores Androgénicos/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Mapeo Cromosómico , Femenino , Disgenesia Gonadal 46 XY/genética , Humanos , Masculino , Datos de Secuencia Molecular , FenotipoRESUMEN
We previously reported a subject with 46,XX true hermaphroditism who had a 46,X,del(X) karyotype and Y-chromosomal sequences in genomic DNA. We hypothesized that the Y-chromosomal sequences were translocated to the deleted X chromosome and that the incomplete testis determination of this individual was the result of inactivation of the translocated X chromosome. In situ hybridization studies demonstrated that the Y-chromosomal sequences were located on the distal portion of the short arm of the deleted X chromosome. Investigation of the replication of the X chromosome, using a modified R-banding technique and localization of Y-chromosomal sequences by in situ hybridization, showed that the translocated X chromosome was late replicating in all 100 EBV-transformed lymphoblasts that were examined. By contrast, when cells from a subject with 46,XX maleness were studied, the translocated X chromosome was late replicating in only 21 of 47 cells. As the late-replicating X chromosome is presumed to be the inactive X chromosome, selection of cells in which the Y-bearing X chromosome has been inactivated may play a role in the incomplete testis determination in subjects with "Y-positive" 46,XX true hermaphroditism.
Asunto(s)
Trastornos del Desarrollo Sexual/genética , Aberraciones Cromosómicas Sexuales , Cromosoma X , Cromosoma Y , Mapeo Cromosómico , Femenino , Humanos , Hibridación in Situ , Cariotipificación , Linfocitos/patología , Masculino , Ovario , TestículoRESUMEN
We report on a group of 9 subjects who had a 46,XY karyotype, ambiguous genitalia, abnormalities of sexual duct formation, and lack of gonadal tissue on one or both sides. This is sometimes referred to as "embryonic testicular regression." Previous investigators have suggested that this condition results from loss of testes at a critical stage in development. We examined the possibility that the "embryonic testicular regression" is part of the clinical spectrum of 46,XY gonadal dysgenesis. Four subjects totally lacked gonadal tissue, three of them having ambiguous genitalia, and one a micropenis. The development of incongruous sexual ducts (presence of Müllerian ducts in the subject with micropenis, and absence of Müllerian and Wolffian ducts in two subjects with ambiguous genitalia) suggests that the embryonic gonads were intrinsically functionally abnormal before their disappearance. Five subjects had unilateral gonadal tissue, ambiguous genitalia, and a mix of Wolffian and Müllerian structures. The development of incongruous sexual ducts in 3 of them, the presence of ambiguous external genitalia in 5, and the presence of abnormal gonadal histology in 2 patients all indicate an underlying abnormality of gonadal differentiation in these subjects. The occurrence of testicular regression in several subjects in the family of one patient suggests a genetic basis for the condition. The presence of multiple congenital anomalies in other subjects in our study suggests either a mutation in a single gene that functions in several developmental pathways, or a defect of multiple genes that might be the result of a chromosome deletion.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Disgenesia Gonadal 46 XY/embriología , Conductos Paramesonéfricos/patología , Testículo/embriología , Conductos Mesonéfricos/patología , Anomalías Múltiples/patología , Preescolar , Femenino , Genitales Femeninos/patología , Disgenesia Gonadal 46 XY/patología , Gónadas/patología , Humanos , Lactante , Masculino , Pene/anomalías , Análisis para Determinación del Sexo , Testículo/fisiopatología , Cromosoma YRESUMEN
The condition termed 46,XY complete gonadal dysgenesis is characterized by the lack of testicular determination with resulting streak gonads, normal Mullerian structures, and female external genitalia. In the partial form, there is incomplete testicular determination with a wide range in the degree of ambiguous genitalia and sexual duct development. We evaluated a kindred in which a partial form of 46,XY gonadal dysgenesis occurred in four subjects from two generations. Pedigree analysis indicated an X-linked or possibly an autosomal sex-limited mode of inheritance. All affected subjects were ascertained because of ambiguous genitalia with minimal virilization. At 10 days of age, the proband had a subnormal plasma level of testosterone, and at 4 months, there was no rise in plasma T after stimulation with hCG. At laparotomy, a dysgenetic gonad was found on the right side, but no gonad was found on the left side. A vas deferens was present on the right, indicating the presence of functional Leydig cells early in fetal life. In the other affected subjects, gonadal tissue was also limited to one side of the abdomen and showed poorly developed seminiferous tubules. The sex-determining region Y gene, which encodes the testis-determining factor, was present and unaltered in the genomic DNA of all affected subjects. Duplication of the distal short arm of the X-chromosome has been associated with 46,XY complete gonadal dysgenesis in some patients. In our studies, Southern blot analysis revealed that sequences of the distal short arm of the X-chromosome (DXS9 to DXS84) were present in single copy, excluding a large duplication in this area of the X. Several kindreds with familial 46,XY complete gonadal dysgenesis have been reported; five of them had evidence of an X-linked mode of inheritance. Our study of a kindred with 46,XY partial gonadal dysgenesis further supports the role of an X chromosome gene in testicular determination. Evidence of some fetal Leydig cell function in the affected subjects of our report suggests that mutations of the putative X-chromosome gene can result in a partial as well as complete defect in testicular determination.
Asunto(s)
Ligamiento Genético , Disgenesia Gonadal 46 XY/genética , Cromosoma X , Southern Blotting , Desarrollo Infantil , Preescolar , Mapeo Cromosómico , Femenino , Genes Dominantes , Disgenesia Gonadal 46 XY/patología , Disgenesia Gonadal 46 XY/fisiopatología , Humanos , Laparotomía , Masculino , LinajeRESUMEN
The dose of glucocorticoid was evaluated in the treatment of 19 patients with salt-losing congenital adrenal hyperplasia due to complete or nearly complete 21-hydroxylase deficiency. In most cases, follow-up was from infancy to puberty. The dose of steroid was expressed as oral cortisol (mg/m2 body surface area/24 hours); the equivalent doses of the various glucocorticoid preparations was as follows: 100 mg oral cortisol = 120 mg oral cortisone acetate = 25 mg oral prednisone = 50 mg intramuscular cortisol = 60 mg intramuscular cortisone acetate. The dose of glucocorticoid producing good laboratory and clinical control varied significantly with age. The dose fell from 26 mg/m2/24 hours in early infancy to 19 mg/m2/24 hours between 6 and 8 years of age, and then rose to 23-24 mg/m2/hour in adolescence. In addition to these age-related changes, there were large individual variations at each age. Indeed, the values from 4 of the 19 patients were not included in the calculation of the mean because they were more than 3 SD either above or below the mean. For the rest of the patients, the coefficient of variation ranged from 14.5% to 37.2%. It is concluded that glucocorticoid therapy must be adjusted carefully to the age and needs of each patient.
Asunto(s)
Hiperplasia Suprarrenal Congénita , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Glucocorticoides/administración & dosificación , 17-Cetosteroides/orina , Administración Oral , Adolescente , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/etiología , Hiperplasia Suprarrenal Congénita/orina , Determinación de la Edad por el Esqueleto , Factores de Edad , Estatura/efectos de los fármacos , Superficie Corporal , Niño , Preescolar , Ritmo Circadiano , Femenino , Estudios de Seguimiento , Glucocorticoides/clasificación , Glucocorticoides/farmacocinética , Glucocorticoides/farmacología , Glucocorticoides/uso terapéutico , Humanos , Inyecciones Intramusculares , Masculino , Equivalencia TerapéuticaRESUMEN
The condition of 46,XX maleness is characterized by testicular development in subjects who have two X chromosomes but who lack a normal Y chromosome. Several etiologies have been proposed to explain 46,XX maleness: 1) translocation of the testis-determining factor from the Y to the X chromosome, 2) mutation in an autosomal or X chromosome gene which permits testicular determination in the absence of TDF, and 3) undetected mosaicism with a Y-bearing cell line. We evaluated 10 affected subjects who were ascertained for different reasons and who had several distinct phenotypes. Six subjects had inherited sequences from the short arm of the Y chromosome including the sex-determining region Y gene (SRY). Five of the subjects were pubertal at the time of evaluation and had a phenotype similar to that of Klinefelter syndrome with evidence of Sertoli cell and Leydig cell dysfunction. One subject had evidence from Southern blot analysis and in situ hybridization for the presence of an intact Y chromosome in approximately 1% of cells. Three subjects lacked Y sequences by Southern blot analysis and by polymerase chain reaction amplification of SRY. These subjects were ascertained in the newborn period because of congenital anomalies. One had multiple anomalies including cardiac abnormalities; one had cardiac anomalies alone; and one had ambiguous genitalia. Our data confirm the genetic heterogeneity of 46,XX maleness, in which some subjects have SRY while other subjects lack it. In addition, there is phenotypic heterogeneity among subjects who lack SRY suggesting that there is also genetic heterogeneity within this subgroup.