Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Genetics ; 214(2): 467-477, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31836612

RESUMEN

XY C57BL/6J (B6) mice harboring a Mus musculus domesticus-type Y chromosome (Y POS ), known as B6.Y POS mice, commonly undergo gonadal sex reversal and develop as phenotypic females. In a minority of cases, B6.Y POS males are identified and a proportion of these are fertile. This phenotypic variability on a congenic B6 background has puzzled geneticists for decades. Recently, a B6.Y POS colony was shown to carry a non-B6-derived region of chromosome 11 that protected against B6.Y POS sex reversal. Here. we show that a B6.Y POS colony bred and archived at the MRC Harwell Institute lacks the chromosome 11 modifier but instead harbors an ∼37 Mb region containing non-B6-derived segments on chromosome 13. This region, which we call Mod13, protects against B6.Y POS sex reversal in a proportion of heterozygous animals through its positive and negative effects on gene expression during primary sex determination. We discuss Mod13's influence on the testis determination process and its possible origin in light of sequence similarities to that region in other mouse genomes. Our data reveal that the B6.Y POS sex reversal phenomenon is genetically complex and the explanation of observed phenotypic variability is likely dependent on the breeding history of any local colony.


Asunto(s)
Disgenesia Gonadal 46 XY/genética , Procesos de Determinación del Sexo/genética , Cromosoma Y/genética , Animales , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 13/metabolismo , Proteínas de Unión al ADN/genética , Trastornos del Desarrollo Sexual/genética , Trastornos del Desarrollo Sexual/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica/genética , Genoma , Disgenesia Gonadal 46 XY/metabolismo , Gónadas/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Nucleares/genética , Ovario/metabolismo , Testículo/metabolismo , Factores de Transcripción/genética
2.
Gene ; 718: 144072, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31446095

RESUMEN

Disorders of sex development (DSDs) are congenital conditions in which chromosomal, gonadal and sex is atypical. It is difficult to diagnose and manage patients with DSD in clinical practice, and the molecular etiology of DSD is still not completely understood. Here, we identified two novel pathogenic mutations from three unrelated Chinese patients with 46,XY complete gonadal dysgenesis (CGD) that is a clinical subgroup of DSD by whole exome sequencing. A novel mutation in the SRY gene (c.161delG) was identified in the first patient, and the second patient carried a novel missense mutation in the MAP3K1 gene (c.2117T>G). Bioinformatics analysis found that the deletion of SRY (c.161delG) led to a premature stop codon at amino acid 59 in the SRY protein, which resulted in lacking the DNA binding domain of SRY protein. Functional studies found that the missense mutation in the MAP3K1 gene (c.2117T>G) could interfere with the gene function through increasing the phosphorylation of the downstream targets of MAP3K1, ERK1/2 and p38, which resulted in reducing testis-determining factor SOX9 expression and increasing ovary-promoting factor ß-catenin activity. According to the American college of medical genetics and genomics (ACMG) standards and guidelines, these mutations were categorized as "pathogenic" mutations. Thus, our findings provide two novel pathogenic mutations associated with 46,XY CGD that can improve the etiological diagnosis for 46,XY CGD. ABBREVIATIONS.


Asunto(s)
Secuencia de Bases , Disgenesia Gonadal 46 XY , Quinasa 1 de Quinasa de Quinasa MAP , Mutación Missense , Eliminación de Secuencia , Adulto , Pueblo Asiatico , Femenino , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal 46 XY/patología , Humanos , Quinasa 1 de Quinasa de Quinasa MAP/genética , Quinasa 1 de Quinasa de Quinasa MAP/metabolismo , Sistema de Señalización de MAP Quinasas/genética , Masculino , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Proteína de la Región Y Determinante del Sexo/genética , Proteína de la Región Y Determinante del Sexo/metabolismo
3.
Fertil Steril ; 111(6): 1226-1235.e1, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30922653

RESUMEN

OBJECTIVE: To identify the genetic cause of a pedigree with four patients with 46,XY pure gonadal dysgenesis (PGD). DESIGN: Genetic mutation study. SETTING: Academic medical center. PATIENT(S): Four first cousins, from three households of a Chinese pedigree, affected by 46,XY PGD. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The patients were studied from clinical and genetic perspectives. Whole-genome sequencing was conducted in family members. RESULT(S): Four first cousins in the third generation were affected by 46,XY PGD. A specific familial characteristic was the prevalence of as high as 100% of gonadal tumors in patients. Whole-genome sequencing identified a new ferritin heavy chain-like 17 (FTHL17) mutation, c.GA442_443TT (p.E148L), which has the potential to interfere with protein function and cause 46,XY PGD. Moreover, the location (Xp21.2) of the FTHL17 gene proves that the family is X-linked recessive. In vitro functional study revealed that the perturbation of FTHL17 caused the decrease of protein expression and cell proliferation. CONCLUSION(S): We describe the first 46,XY PGD pedigree that may be attributed to mutations of the FTHL17 gene. We speculated that the FTHL17 gene is involved in the testis-determining pathway and tumorigenesis.


Asunto(s)
Apoferritinas/genética , Disgenesia Gonadal 46 XY/genética , Mutación , Neoplasias de Tejido Gonadal/genética , Adolescente , Adulto , Apoferritinas/metabolismo , Proliferación Celular , Análisis Mutacional de ADN , Femenino , Predisposición Genética a la Enfermedad , Disgenesia Gonadal 46 XY/diagnóstico , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal 46 XY/cirugía , Células HEK293 , Herencia , Humanos , Neoplasias de Tejido Gonadal/diagnóstico , Neoplasias de Tejido Gonadal/metabolismo , Neoplasias de Tejido Gonadal/cirugía , Linaje , Fenotipo
4.
Hum Mutat ; 39(12): 2097-2109, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30298535

RESUMEN

In humans, mutations of Desert Hedgehog gene (DHH) have been described in patients with 46,XY gonadal dysgenesis (GD), associated or not with polyneuropathy. In this study, we describe two patients diagnosed with GD, both harboring novel DHH compound heterozygous mutations p.[Tyr176*];[Asn337Lysfs*24] and p.[Tyr176*];[Glu212Lys]. To investigate the functional consequences of p.(Asn337Lysfs*24) and p.(Glu212Lys) mutations, located within the C-terminal part of DHh on auto-processing, we performed in vitro cleavage assays of these proteins in comparison with Drosophila melanogaster Hedgehog (Hh). We found that p.(Glu212Lys) mutation retained 50% of its activity and led to a partially abolished DHh auto-processing. In contrast, p.(Asn337Lysfs*24) mutation resulted in a complete absence of auto-proteolysis. Furthermore, we found a different auto-processing profile between Drosophila Hh and human DHh, which suggests differences in the processing mechanism between the two species. Review of the literature shows that proven polyneuropathy and GD is associated with complete disruption of DHh-N, whereas disruption of the DHh auto-processing is only described with GD. We propose a model that may explain the differences between Schwann and Leydig cell development by autocrine versus paracrine DHh signaling. To our knowledge, this is the first study investigating the effect of DHH mutations on DHh in vitro auto-processing.


Asunto(s)
Proteínas de Drosophila/metabolismo , Disgenesia Gonadal 46 XY/genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Mutación , Animales , Preescolar , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Disgenesia Gonadal 46 XY/metabolismo , Proteínas Hedgehog/química , Heterocigoto , Humanos , Masculino , Dominios Proteicos , Proteolisis , Especificidad de la Especie , Adulto Joven
7.
Arch Endocrinol Metab ; 60(1): 79-84, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26909487

RESUMEN

The male hypogonadism-related bone mass loss is often under diagnosed. Peak bone mass is severely affected if the hypogonadism occurs during puberty and is left untreated. We present an interesting; almost bizarre case of a male with non-functional testes early during childhood and undiagnosed and untreated hypogonadism until his fifth decade of life. Forty six year male is referred for goitre, complaining of back pain. Phenotype suggested intersexuality: gynoid proportions, micropenis, no palpable testes into the scrotum, no facial or truncal hair. His medical history had been unremarkable until the previous year when primary hypothyroidism was diagnosed and levothyroxine replacement was initiated. Later, he was diagnosed with ischemic heart disease, with inaugural unstable angina. On admission, the testosterone was 0.2 ng/mL (normal: 1.7-7.8 ng/mL), FSH markedly increased (56 mUI/mL), with normal adrenal axis, and TSH (under thyroxine replacement). High bone turnover markers, and blood cholesterol, and impaired glucose tolerance were diagnosed. The testes were not present in the scrotum. Abdominal computed tomography suggested bilateral masses of 1.6 cm diameter within the abdominal fat that were removed but no gonadal tissue was confirmed histopathologically. Vanishing testes syndrome was confirmed. The central DXA showed lumbar bone mineral density of 0.905 g/cm2, Z-score of -2.9SD. The spine profile X-Ray revealed multiple thoracic vertebral fractures. Alendronate therapy together with vitamin D and calcium supplements and trans-dermal testosterone were started. Four decades of hypogonadism associate increased cardiac risk, as well as decreased bone mass and high fracture risk.


Asunto(s)
Disgenesia Gonadal 46 XY/complicaciones , Hipogonadismo/complicaciones , Isquemia Miocárdica/complicaciones , Osteoporosis/complicaciones , Testículo/anomalías , Disgenesia Gonadal 46 XY/diagnóstico por imagen , Disgenesia Gonadal 46 XY/metabolismo , Humanos , Hipogonadismo/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/metabolismo , Osteoporosis/diagnóstico por imagen , Osteoporosis/metabolismo , Radiografía , Factores de Riesgo , Testículo/diagnóstico por imagen , Testículo/metabolismo , Testosterona/sangre , Tirotropina/sangre
8.
Horm Res Paediatr ; 80(3): 163-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23920000

RESUMEN

BACKGROUND: The steroidogenic acute regulatory protein (StAR) is essential for steroidogenesis by mediating cholesterol transfer into mitochondria. Inactivating StAR mutations cause lipoid congenital adrenal hyperplasia. OBJECTIVE AND METHODS: To identify causative mutations in a patient presenting with adrenal failure during early infancy. The objective was to study the functional and structural consequences of the novel StAR mutation p.Trp147Arg in a Turkish patient detected in compound heterozygosity with the p.Glu169Lys mutation. RESULTS: Transient in vitro expression of the mutant proteins together with P450 side-chain cleavage enzyme, adrenodoxin, and adrenodoxin reductase yielded severely diminished cholesterol conversion of the p.Trp147Arg mutant. The previously described p.Glu169Lys mutant led to significantly lower cholesterol conversion than wild-type StAR protein. As derived from three-dimensional protein modeling, the residue W147 is stabilizing the C-terminal helix in a closed conformation hereby acting as gatekeeper of the ligand cavity of StAR. CONCLUSIONS: The novel mutation p.Trp147Arg causes primary adrenal insufficiency and complete sex reversal in the 46,XY patient. Clinical disease, in vitro studies and three-dimensional protein modeling of the mutation p.Trp147Arg underscore the relevance of this highly conserved residue for StAR protein function.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Insuficiencia Suprarrenal/congénito , Trastorno del Desarrollo Sexual 46,XY , Disgenesia Gonadal 46 XY , Modelos Moleculares , Mutación Missense , Fosfoproteínas , Hiperplasia Suprarrenal Congénita/genética , Hiperplasia Suprarrenal Congénita/metabolismo , Insuficiencia Suprarrenal/genética , Insuficiencia Suprarrenal/metabolismo , Adrenodoxina/genética , Adrenodoxina/metabolismo , Sustitución de Aminoácidos , Animales , Células COS , Preescolar , Chlorocebus aethiops , Colesterol/genética , Colesterol/metabolismo , Trastorno del Desarrollo Sexual 46,XY/genética , Trastorno del Desarrollo Sexual 46,XY/metabolismo , Ferredoxina-NADP Reductasa/genética , Ferredoxina-NADP Reductasa/metabolismo , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Humanos , Lactante , Masculino , Fosfoproteínas/química , Fosfoproteínas/inmunología , Fosfoproteínas/metabolismo , Relación Estructura-Actividad , Turquía
9.
DNA Cell Biol ; 32(9): 524-30, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23786321

RESUMEN

Mutations of Desert hedgehog (DHH) have been associated to 46,XY pure gonadal dysgenesis (PGD) and to mixed gonadal dysgenesis (MGD); however, there have been no functional studies of mutations described in DHH. To determine if mutations p.L162P and Δ1086delG yield functional impairment, we performed in vitro and in silico analysis of both DHH mutants. In complementary DNA of DHH, we performed site-directed mutagenesis, which was confirmed by DNA sequencing. Protein extracts were obtained from HEK293cells transfected with different constructs and analyzed by Western blot; besides, densitometric analysis of chemiluminescent signals was performed. In addition, the structure of the wt-DHH and its two mutant proteins was inferred using in silico protein molecular modeling. In the Western blot analysis, we observed the absence of signal for p.L162P in DHH-N and a diminished signal for Δ1086delG in DHH-C, when compared to wt-DHH. Protein modeling showed notable conformational changes for the side chains of p.L162P, while the secondary structure was drastically modified in Δ1086delG, when compared to wt-DHH. To our knowledge, this is the first study focused to determine by in vitro studies, the effect of two specific mutations in DHH associated with 46,XY PGD and MGD. Our results suggest that both mutations have a deleterious effect on the expression of the DHH mutant proteins.


Asunto(s)
Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal Mixta/genética , Proteínas Hedgehog/metabolismo , Mutación Puntual , Sustitución de Aminoácidos , Biología Computacional , Predisposición Genética a la Enfermedad , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal Mixta/metabolismo , Células HEK293 , Proteínas Hedgehog/genética , Humanos , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Estabilidad Proteica , Estructura Secundaria de Proteína
10.
Dev Cell ; 23(5): 1032-42, 2012 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-23102581

RESUMEN

Male sex determination in mammals is induced by Sry, a gene whose regulation is poorly understood. Here we show that mice mutant for the stress-response gene Gadd45g display complete male-to-female sex reversal. Gadd45g and Sry have a strikingly similar expression pattern in the genital ridge, and they are coexpressed in gonadal somatic cells. In Gadd45g mutants, Sry expression is delayed and reduced, and yet Sry seemed to remain poised for expression, because its promoter is demethylated on schedule and is occupied by active histone marks. Instead, p38 MAPK signaling is impaired in Gadd45g mutants. Moreover, the transcription factor GATA4, which is required for Sry expression, binds to the Sry promoter in vivo in a MAPK-dependent manner. The results suggest that a signaling cascade, involving GADD45G → p38 MAPK → GATA4 → SRY, regulates male sex determination.


Asunto(s)
Proteínas Portadoras/metabolismo , Procesos de Determinación del Sexo/fisiología , Proteína de la Región Y Determinante del Sexo/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Proteínas Portadoras/genética , Metilación de ADN , Femenino , Factor de Transcripción GATA4/metabolismo , Regulación del Desarrollo de la Expresión Génica , Genes sry , Disgenesia Gonadal 46 XY/embriología , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Ratones Mutantes , Ratones Transgénicos , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Procesos de Determinación del Sexo/genética , Proteína de la Región Y Determinante del Sexo/genética , Testículo/embriología , Testículo/metabolismo
11.
Dev Cell ; 23(5): 1020-31, 2012 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-23102580

RESUMEN

Loss of the kinase MAP3K4 causes mouse embryonic gonadal sex reversal due to reduced expression of the testis-determining gene, Sry. However, because of widespread expression of MAP3K4, the cellular basis of this misregulation was unclear. Here, we show that mice lacking Gadd45γ also exhibit XY gonadal sex reversal caused by disruption to Sry expression. Gadd45γ is expressed in a dynamic fashion in somatic cells of the developing gonads from 10.5 days postcoitum (dpc) to 12.5 dpc. Gadd45γ and Map3k4 genetically interact during sex determination, and transgenic overexpression of Map3k4 rescues gonadal defects in Gadd45γ-deficient embryos. Sex reversal in both mutants is associated with reduced phosphorylation of p38 MAPK and GATA4. In addition, embryos lacking both p38α and p38ß also exhibit XY gonadal sex reversal. Taken together, our data suggest a requirement for GADD45γ in promoting MAP3K4-mediated activation of p38 MAPK signaling in embryonic gonadal somatic cells for testis determination in the mouse.


Asunto(s)
Proteínas Portadoras/metabolismo , MAP Quinasa Quinasa Quinasa 4/metabolismo , Proteína Quinasa 11 Activada por Mitógenos/metabolismo , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Proteína de la Región Y Determinante del Sexo/genética , Testículo/embriología , Testículo/metabolismo , Animales , Proteínas Portadoras/genética , Metilación de ADN , Femenino , Factor de Transcripción GATA4/metabolismo , Regulación del Desarrollo de la Expresión Génica , Genes sry , Disgenesia Gonadal 46 XY/embriología , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Péptidos y Proteínas de Señalización Intracelular , MAP Quinasa Quinasa Quinasa 4/deficiencia , MAP Quinasa Quinasa Quinasa 4/genética , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Quinasa 11 Activada por Mitógenos/deficiencia , Proteína Quinasa 11 Activada por Mitógenos/genética , Proteína Quinasa 14 Activada por Mitógenos/deficiencia , Proteína Quinasa 14 Activada por Mitógenos/genética , Modelos Biológicos , Procesos de Determinación del Sexo/genética , Procesos de Determinación del Sexo/fisiología
12.
Horm Res Paediatr ; 78(3): 188-92, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22441105

RESUMEN

BACKGROUND: SRY, located on the Y chromosome, is one of the key genes involved in human sex determination. SRY mutations are responsible for 10-15% of all cases of 46,XY gonadal dysgenesis (GD) but are rarely implicated in the pathogenesis of mixed GD. METHODS: SRY was analyzed by sequence analysis of DNA extracted from blood leukocytes. SRY activity was evaluated by SOX9 immunostaining, one of the targets of SRY. RESULTS: We report a case of mixed GD due to a novel SRY point mutation in a patient with a 46,XY karyotype, without mosaicism or submicroscopic genomic imbalances. Hormonal studies showed low anti-müllerian hormone and histological examination of the gonads showed a streak gonad on the right side and a left dysgenetic testis, thus permitting the diagnosis of mixed GD. Immunostaining for SOX9, a target of SRY, was positive in nuclei of Sertoli and epididymal cells in the left gonad and negative on the right, thus indicating asymmetric activation of SRY. CONCLUSION: Mixed GD can result from SRY mutations without mosaicism, neither in peripheral blood, nor within the gonads. The asymmetric effect of the point mutation implies the presence of local factors modulating SRY expression or action.


Asunto(s)
Disgenesia Gonadal 46 XY , Mosaicismo , Factor de Transcripción SOX9/metabolismo , Proteína de la Región Y Determinante del Sexo , Preescolar , Femenino , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Humanos , Masculino , Proteína de la Región Y Determinante del Sexo/genética , Proteína de la Región Y Determinante del Sexo/metabolismo
13.
J Med Genet ; 48(12): 825-30, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22051515

RESUMEN

BACKGROUND: The early gonad is bipotential and can differentiate into either a testis or an ovary. In XY embryos, the SRY gene triggers testicular differentiation and subsequent male development via its action on a single gene, SOX9. The supporting cell lineage of the bipotential gonad will differentiate as testicular Sertoli cells if SOX9 is expressed and conversely will differentiate as ovarian granulosa cells when SOX9 expression is switched off. RESULTS: Through copy number variation mapping this study identified duplications upstream of the SOX9 gene in three families with an isolated 46,XX disorder of sex development (DSD) and an overlapping deletion in one family with two probands with an isolated 46,XY DSD. The region of overlap between these genomic alterations, and previously reported deletions and duplications at the SOX9 locus associated with syndromic and isolated cases of 46,XX and 46,XY DSD, reveal a minimal non-coding 78 kb sex determining region located in a gene desert 517-595 kb upstream of the SOX9 promoter. CONCLUSIONS: These data indicate that a non-coding regulatory region critical for gonadal SOX9 expression and subsequent normal sex development is located far upstream of the SOX9 promoter. Its copy number variations are the genetic basis of isolated 46,XX and 46,XY DSDs of variable severity (ranging from mild to complete sex reversal). It is proposed that this region contains a gonad specific SOX9 transcriptional enhancer(s), the gain or loss of which results in genomic imbalance sufficient to activate or inactivate SOX9 gonadal expression in a tissue specific manner, switch sex determination, and result in isolated DSD.


Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/genética , Disgenesia Gonadal 46 XY/genética , Gonadoblastoma/genética , Secuencias Reguladoras de Ácidos Nucleicos , Factor de Transcripción SOX9/genética , Trastornos del Desarrollo Sexual 46, XX/metabolismo , Trastornos del Desarrollo Sexual 46, XX/patología , Alelos , Niño , Mapeo Cromosómico , Hibridación Genómica Comparativa , Variaciones en el Número de Copia de ADN , Femenino , Duplicación de Gen , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal 46 XY/patología , Gonadoblastoma/patología , Haplotipos , Humanos , Lactante , Masculino , Linaje , Factor de Transcripción SOX9/metabolismo , Proteína de la Región Y Determinante del Sexo/genética , Proteína de la Región Y Determinante del Sexo/metabolismo
14.
Fertil Steril ; 96(4): 851-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21868002

RESUMEN

OBJECTIVE: To investigate the familial segregation, role, and function of a novel SRY missense mutation c.347T>C in two half-sisters affected by 46,XY complete gonadal dysgenesis (CDG) compatible with a successful pregnancy outcome. DESIGN: Phenotypic, mutational, and functional study. SETTING: Academic research unit. PATIENT(S): Two half-sisters, their common father, and 100 healthy control individuals. INTERVENTION(S): Chromosome, molecular cytogenetic analysis, and Sanger sequencing of the SRY gene in blood lymphocytes of the proband, her affected half-sister, and in inflammatory tissue of the father postmortem. Cloning and expression of high mobility group box carboxy-terminal domains of Sry and electrophoretic mobility shift assay were performed. MAIN OUTCOME MEASURE(S): Not applicable. RESULT(S): A novel SRY missense mutation c.347T>C (p.Leu116Ser) was identified in two half-sisters and segregates with the CGD phenotype. It is present in the common healthy father in a mosaic state. Functional analyses demonstrate the pathogenic effect of the mutation by a strong reduction of DNA affinity for the mutant p.Leu116Ser SRY protein. CONCLUSION(S): The missense mutation c.347T>C in the high mobility group domain of SRY causes 46,XY CGD. Paternal gonadal mosaicism is likely to explain the familial occurrence of 46,XY CGD suggesting a de novo mutational event during the early stages of embryonic development. This novel mutation is compatible with a successful pregnancy outcome.


Asunto(s)
ADN/genética , Genes sry/genética , Disgenesia Gonadal 46 XY/genética , Mutación Missense/genética , Adolescente , Adulto , Secuencia de Aminoácidos , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Disgenesia Gonadal 46 XY/metabolismo , Dominios HMG-Box/genética , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mosaicismo , Embarazo , Adulto Joven
15.
Pediatr Dev Pathol ; 14(6): 445-59, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21692598

RESUMEN

Patients with XY gonadal dysgenesis are at increased risk of developing gonadal tumors. The etiology of several cases of XY gonadal dysgenesis remains unknown, but X/XY gonadal mosaicism has been hypothesized to play a role. At the histologic level, the presence of persistent primitive sex cords containing immature germ cells in dysgenetic gonads (an entity called undifferentiated gonadal tissue, or UGT) was recently described, and these immature germ cells are thought to be at risk of neoplastic transformation. To further investigate both these aspects, we retrospectively studied the gonads from 30 patients with pure (22) and mixed (8) gonadal dysgenesis. Cytogenetic analyses performed on 35 gonads revealed that structurally abnormal Y chromosomes were lost in a majority of cells from the gonads, explaining the gonadal dysgenesis of patients bearing a rearranged Y chromosome. On the other hand, normal Y chromosomes were less often lost in gonads of patients with gonadal dysgenesis. At the histologic level, 43 of the 51 gonads presented areas characteristic of a streak; 13 of these streak gonads also presented areas of UGT. Structures resembling sex cords but without germ cells were found in many of the streaks not containing UGT, suggesting that UGT was initially present. Of the 13 gonads containing both UGT and a streak, 9 developed a tumor. The proximity of UGT with the tumors as well as the immunostaining patterns (PLAP+, OCT3/4+, and CD117/KIT+) suggests that germ cells found in UGT are a risk factor for gonadal tumors.


Asunto(s)
Inestabilidad Cromosómica , Cromosomas Humanos Y , Disgenesia Gonadal 46 XY/patología , Gonadoblastoma/patología , Neoplasias Ováricas/patología , Neoplasias Testiculares/patología , Fosfatasa Alcalina/metabolismo , Biomarcadores de Tumor/metabolismo , Diferenciación Celular , Femenino , Proteínas Ligadas a GPI/metabolismo , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Gonadoblastoma/genética , Gonadoblastoma/metabolismo , Humanos , Hibridación Fluorescente in Situ , Isoenzimas/metabolismo , Cariotipificación , Masculino , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Estudios Retrospectivos , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo
16.
Differentiation ; 82(1): 18-27, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21592645

RESUMEN

SRY on the Y-chromosome acts as a transcription factor to initiate testicular differentiation in mammals. Sox9 is a SRY target gene, upregulated immediately after Sry expression, and plays a key role in testicular differentiation. In the present study, we examined the expression of SRY and SOX9 proteins in the B6.Y(TIR) gonad, which undergoes partial or complete sex reversal. The results show that the ontogeny of SRY expression in the B6.Y(TIR) gonad was comparable with that in the B6.XY gonad. On the other hand, while SOX9 expression immediately followed SRY expression in the B6.XY gonad, it was considerably delayed compared to SRY expression in the B6.Y(TIR) gonad or SOX9 expression in the B6.XY gonad. Although SOX9 expression reached the entire gonad at a time point, it was downregulated and became restricted to the central area in which testis cords were organized. MIS, a marker of Sertoli cells, appeared only in well-organized testis cords. We speculate that the SRY protein from the Y(TIR)-chromosome is inefficient in upregulating the Sox9 gene on the B6 background, allowing the initiation of ovarian differentiation.


Asunto(s)
Diferenciación Celular , Regulación del Desarrollo de la Expresión Génica , Disgenesia Gonadal 46 XY , Ovario/citología , Ovario/embriología , Factor de Transcripción SOX9/genética , Proteína de la Región Y Determinante del Sexo/metabolismo , Animales , Femenino , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Gónadas/metabolismo , Masculino , Ratones , Receptores de Péptidos/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Transcripción SOX9/metabolismo , Testículo/citología , Testículo/embriología , Testículo/metabolismo , Regulación hacia Arriba
17.
J Clin Endocrinol Metab ; 95(7): 3418-27, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20410220

RESUMEN

CONTEXT: Undervirilization in males, i.e. 46,XY disordered sex development (46,XY DSD), is commonly caused by either lack of androgen action due to mutant androgen receptor (AR) or deficient androgen synthesis, e.g. due to mutations in 17alpha-hydroxylase (CYP17A1). Like all other microsomal cytochrome P450 (CYP) enzymes, CYP17A1 requires electron transfer from P450 oxidoreductase (POR). OBJECTIVE: The objective of the study was to analyze the clinical and biochemical phenotype in a 46,XY individual carrying concomitant POR and AR mutations and to dissect their impact on phenotypic expression. METHODS: We characterized the clinical and biochemical phenotype, genetic identification, and functional analysis of POR missense mutation by yeast micrososomal coexpression assays for CYP17A1, CYP21A2 and CYP19A1 activities. RESULTS: The patient presented neonatally with 46,XY DSD and was diagnosed as partial androgen insensitivity syndrome carrying a disease causing AR mutation (p.Q798E). She was raised as a girl and gonadectomized at the age of 4 yr. At 9 yr progressive clitoral enlargement prompted reassessment. Urinary steroid analysis was indicative of POR deficiency, but surprisingly androgen production was normal. Genetic analysis identified compound heterozygous POR mutations (p.601fsX12/p.Y607C). In vitro analysis confirmed p.Y607C as a pathogenic mutation with differential inhibition of steroidogenic CYP enzymes. CONCLUSION: Both mutant AR and POR are likely to contribute to the neonatal presentation with 46,XY DSD. Virilization at the time of adrenarche appears to suggest an age-dependent, diminishing disruptive effect of both mutant proteins. This case further highlights the importance to assess both gonadal and adrenal function in patients with 46,XY DSD.


Asunto(s)
Adrenarquia/genética , Disgenesia Gonadal 46 XY/genética , Oxidorreductasas/genética , Receptores Androgénicos/genética , Virilismo/genética , Adrenarquia/metabolismo , Western Blotting , Niño , Femenino , Disgenesia Gonadal 46 XY/metabolismo , Humanos , Masculino , Mutación/genética , Oxidorreductasas/metabolismo , Receptores Androgénicos/metabolismo , Desarrollo Sexual/genética , Esteroide 17-alfa-Hidroxilasa/genética , Esteroide 17-alfa-Hidroxilasa/metabolismo , Virilismo/metabolismo
18.
Congenit Anom (Kyoto) ; 50(1): 40-51, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20201967

RESUMEN

XY females are rare individuals who carry a Y chromosome but are phenotypically female. In approximately 80-90% of these cases, there are no mutations in the SRY gene, a testis-determining gene on the short arm of the Y chromosome, and the pathophysiology of XY females without SRY mutation remains unclear. In the present study, we used a molecular data mining technique to analyze the pathophysiology of an XY female with functional SRY and pericentric inversion of the Y chromosome, and compared the results with those of a normal male. Interestingly, upregulations of numerous genes included in the development category of the Biological Process ontology, including genes associated with sex determination and organ morphogenesis, were seen in the patient. Additionally, the transforming growth factor-beta (TGF-beta) signaling pathway and Wnt signaling pathway, in which most cell-cell interactions during embryonic development are involved, were altered. Alterations in the expression of numerous genes at the developmental stage, including alterations at both the gene and pathway levels, may persist as a vestige of anomalies of sex differentiation that presumably began in the fetal period. The present study indicates that a data mining technique using bioinformatics contributes to identification of not only genes responsible for birth defects, but also disorders of sex development (DSD)-specific pathways, and that this kind of analysis is an important tool for clarifying the pathophysiology of human idiopathic XY gonadal dysgenesis. Our findings could serve as one of the basic datasets which will be used for future follow-up investigations.


Asunto(s)
Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Adolescente , Cromosomas Humanos Y , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Redes y Vías Metabólicas/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Aberraciones Cromosómicas Sexuales , Proteína de la Región Y Determinante del Sexo/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación hacia Arriba
19.
Mol Cell Endocrinol ; 299(2): 212-8, 2009 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-19007850

RESUMEN

Mutations of SRY are the cause of 46,XY complete pure gonadal dysgenesis (PGD) in 10-15% of patients. In this study, DNA was isolated and sequenced from blood leukocytes and from paraffin-embedded gonadal tissue in five patients with 46,XY complete PGD. DNA binding capability was analyzed by three different methods. The structure of the full length SRY and its mutant proteins was carried out using a protein molecular model. DNA analysis revealed two mutations and one synonymous polymorphism: in patient #4 a Y96C mutation, and a E156 polymorphism; in patient #5 a S143G mosaic mutation limited to gonadal tissue. We demonstrated, by all methods used, that both mutant proteins reduced SRY DNA binding activity. The three-dimensional structure of SRY suggested that besides the HMG box, the carboxy-terminal region of SRY interacts with DNA. In conclusion, we identified two SRY mutations and a polymorphism in two patients with 46,XY complete PGD, demonstrating the importance of the carboxy-terminal region of SRY in DNA binding activity.


Asunto(s)
Biología Computacional , ADN/metabolismo , Disgenesia Gonadal 46 XY/metabolismo , Proteínas Mutantes/metabolismo , Proteína de la Región Y Determinante del Sexo/metabolismo , Secuencia de Bases , Análisis Mutacional de ADN , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Mutantes/genética , Unión Proteica , Proteína de la Región Y Determinante del Sexo/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...