Análisis clínico y citogenético de un caso de trastorno del desarrollo sexual testicular XX con SRY negativo / Clinical and Cytogenetic Analysis of a Case of SRY-Negative XX Testicular Disorder of Sex Development / Análise clínica e citogenética de um caso de transtorno do desenvolvimento sexual testicular XX com SRY-negativo

Resumen: El trastorno del desarrollo sexual (TDS) testicular XX es una patología que se presenta en un individuo con cariotipo 46,XX con un fenotipo anatómico de genitales externos masculinos, que pueden variar desde la normalidad hasta la ambigüedad genital. Clínicamente se han descrito dos subgrupos de hombres 46,XX con SRY-negativos y SRY-positivos, dependiendo de la presencia o no del gen SRY que normalmente se encuentra en el cromosoma Y participando en la determinación testicular. En este artículo se describen los antecedentes personales y los hallazgos clínicos de un infante con anomalías del meato urinario en el cual se identificó un complemento cromosómico 46,XX. También, se realizó hibridación in situ fluorescente en linfocitos de sangre periférica que demostró la ausencia del gen SRY y confirmó la presencia de dos cromosomas X.

Abstract XX testicular disorder of sex development (DSD) is a pathology that occurs in an individual with a 46,XX karyotype and an anatomical phenotype of male external genitalia, which may vary from normal to ambiguous. Clinically, two subgroups of SRY-negative and SRY-positive, 46, XX men have been described, depending on the presence of the SRY gene that is normally found on the Y chromosome participating in testicular determination. This article describes the personal history and clinical findings of an infant with urethral meatus abnormalities in whom a 46,XX chromosome set was identified. Also, fluorescent in situ hybridization was performed in peripheral blood lymphocytes which demonstrated the absence of the SRY gene and confirmed the presence of two X chromosomes.

Resumo: O transtorno do desenvolvimento sexual (TDS) testicular XX é uma patologia apresentada em um indivíduo com cariótipo 46,XX com um fenótipo anatômico de genitais externos masculinos, que podem variar da normalidade à ambiguidade genital. Clinicamente, são descritos dois subgrupos de homens 46,XX com SRY-negativos e SRY-positivos, dependendo da presença ou não do gene SRY que normalmente se encontra em Y cromossomo participando da determinação testicular. Neste artigo, são descritos os antecedentes pessoais e os achados clínicos de uma criança com anomalias de meato urinário em que foi identificado um complemento cromossômico 46,XX. Além disso, foi rea -lizada hibridação in situ fluorescente em linfócitos de sangue periférico que demonstrou a ausência do gene SRY e confirmou a presença de dois cromossomos X.

Three cases of rare SRY-negative 46,XX testicular disorder of sexual development with complete masculinization and a review of the literature

PURPOSE: To identify the clinical characteristics of SRY-negative male patients and genes related to male sex reversal, we performed a retrospective study using cases of 46,XX testicular disorders of sex development with a review of the literature. MATERIALS AND METHODS: SRY-negative cases of 46,XX testicular disorders of sex development referred for cytogenetic analysis from 1983 to 2013 were examined using clinical findings, seminal analyses, basal hormone profiles, conventional cytogenetic analysis and polymerase chain reaction. RESULTS: Chromosome analysis of cultured peripheral blood cells of 8,386 individuals found 19 cases (0.23%) with 46,XX testicular disorders of sex development. The SRY gene was confirmed to be absent in three of these 19 cases (15.8%). CONCLUSION: We report three rare cases of SRY-negative 46,XX testicular disorders of sex development. Genes on autosomes and the X chromosome that may have a role in sex determination were deduced through a literature review. These genes, through differences in gene dosage variation, may have a role in sex reversal in the absence of SRY.