RESUMO
Objetivo: Determinar el grupo RhD fetal a través del estudio del gen RHD en ADN fetal que se encuentra libre en plasma de embarazadas RhD negativo. Método: Se analizó la presencia de los genes RHD, SRY y BGLO en ADNfl obtenido de plasma de 51 embarazadas RhD negativo no sensibilizadas, utilizando una qPCR. Los resultados del estudio genético del gen RHD se compararon con el estudio del grupo sanguíneo RhD realizado por método serológico en muestras de sangre de cordón, y los resultados del estudio del gen SRY fueron cotejados con el sexo fetal determinado por ecografía. Se calcularon la sensibilidad, la especificidad, los valores predictivos y la capacidad discriminativa del método estandarizado. Resultados: El gen RHD estaba presente en el 72,5% de las muestras y el gen SRY en el 55,5%, coincidiendo en un 100% con los resultados del grupo RhD detectado en sangre de cordón y con el sexo fetal confirmado por ecografía, respectivamente. Conclusiones: Fue posible deducir el grupo sanguíneo RhD del feto mediante el estudio del ADN fetal que se encuentra libre en el plasma de embarazadas con un método molecular no invasivo desarrollado y validado para este fin. Este test no invasivo puede ser utilizado para tomar la decisión de administrar inmunoglobulina anti-D solo a embarazadas RhD negativo que portan un feto RhD positivo.
Objective: To determine the fetal RhD group through the study of the RHD gene in fetal DNA found free in plasma of RhD negative pregnant women. Method: The presence of the RHD, SRY and BGLO genes in fetal DNA obtained from plasma of 51 non-sensitized RhD negative pregnant women was analyzed using qPCR. The results of the genetic study of the RHD gene were compared with the RhD blood group study performed by serological method in cord blood samples, and the results of the SRY gene study were compared with the fetal sex determined by ultrasound. Sensitivity, specificity, predictive values and discriminative capacity of the standardized method were calculated. Results: The RHD gene was present in 72.5% of the samples and the SRY gene in 55.5%, coinciding 100% with the results of the RhD group detected in cord blood, and with the fetal sex confirmed by ultrasound, respectively. Conclusions: It was possible to deduce the RhD blood group of the fetus through the study of fetal DNA found free in the plasma of pregnant women with a non-invasive molecular method developed and validated for this purpose. This non-invasive test can be used to make the decision to administer anti-D immunoglobulin only to RhD-negative pregnant women carrying an RhD-positive fetus.
Assuntos
Humanos , Feminino , Gravidez , Sistema do Grupo Sanguíneo Rh-Hr/genética , DNA , Eritroblastose Fetal/diagnóstico , Eritroblastose Fetal/genética , Fenótipo , Diagnóstico Pré-Natal , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Imunoglobulina rho(D) , Genes sry/genética , Eritroblastose Fetal/sangue , Doenças Fetais/diagnóstico , Doenças Fetais/genética , Doenças Fetais/sangue , GenótipoRESUMO
46,XX testicular disorder of sex development is a rare syndrome characterized by an inconsistency between genotype and phenotype. Affected individuals present variant genitalia between male and ambiguous, non-functional testicles, non-obstructive azoospermia, generally accompanied by hypergonadotropic hypogonadism, a condition known for high levels of gonadotrophic hormones. In some cases, disorders of sexual development are diagnosed during puberty. However, a significant number of individuals show physical characteristics common to males that are not clinically suspicious. As a result, patients with the condition may remain undiagnosed. Many individuals with the condition are diagnosed as adults, due to infertility. The present study discusses the case of an individual who underwent karyotyping for sterility and was found to be a 46,XX male. Despite having a female karyotype, the presence of the sex-determining region Y gene explains the manifestation of masculine secondary sex characteristics. This report highlights the importance of genetic evaluation, considering that carriers may present significant complications resulting from the disorder. Based on correct diagnosis, it is possible to improve a carrier's quality of life through multidisciplinary approaches and help them achieve pregnancy through assisted reproductive technology treatments.
Assuntos
Infertilidade Masculina , Doenças Testiculares , Feminino , Genes sry , Pesquisa em Genética , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética , Masculino , Qualidade de Vida , Desenvolvimento Sexual , Doenças Testiculares/diagnóstico , Doenças Testiculares/genéticaRESUMO
Male-to-female sex reversal in horses is a developmental disorder in which phenotypic females have a male genetic constitution. Male-to-female sex reversal is the second most common genetic sex abnormality, after X chromosome monosomy. All male-to-female sex reversal cases studied to date have been found to be infertile. Therefore, a screening test is particularly useful in laboratories doing DNA genotyping in horses. Our laboratory has tested > 209,000 horses for parentage using a panel of microsatellite markers and the sex marker gene amelogenin (AMEL). Suspect XY sex reversal cases are reported females with a male profile by AMEL testing. After routine genotyping, 49 cases were detected and further tested using the sex-determining region Y (SRY) gene, confirming the XY SRY-negative genotype of suspect sex reversal cases. When some inconsistencies arose in the initial result, a molecular panel of X- and Y-linked markers was analyzed for these samples. Of the 49 cases, 33 were confirmed as XY SRY-negative. The remaining 16 cases were identified as false-positives as a result of anomalies of AMEL testing in horses.
Assuntos
Transtornos do Desenvolvimento Sexual/veterinária , Técnicas de Genotipagem/veterinária , Doenças dos Cavalos/diagnóstico , Fatores de Transcrição SOX/genética , Amelogenina/genética , Animais , DNA/genética , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Feminino , Genótipo , Técnicas de Genotipagem/normas , Doenças dos Cavalos/genética , Cavalos , MasculinoRESUMO
The aetiology of congenital bilateral anorchia is unknown. For many years there was speculation of an association between genetic factors and anorchia. We performed different tests in an anorchid boy, 2.5 years old, presented to us with micropenis and absence of both testes, in order to determine any possible factors contributing to the anorchia. Physical examination and hormonal, imaging, chromosomal, and molecular analyses of this case were performed. The basal FSH and LH levels were increased, and their increase in response to gonadotrophin-releasing hormone test was prolonged, while testosterone levels failed to increase after hCG administration. Ultrasonography of the pelvis and magnetic resonance of the abdomen were performed and failed to show any testicular tissue. Lastly, surgical exploration confirmed the absence of testicular structure. Chromosomal analysis revealed a normal male karyotype and molecular analysis did not reveal mutations or polymorphisms in the open reading frame of the SRY gene. Diagnostically, the lack of testosterone response to hCG stimulation is the hormonal hallmark of bilateral congenital anorchia. In addition, according to our case and previous studies, there is lack of association between genetic factors necessary for correct testicular descent and anorchia.