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Background The MLPA (multiplex ligation dependent probe amplification) technique is currently the test most widely used to detect mutations in the Duchenne/Becker muscular dystrophy (DMD) gene in the initial assessment. However, several studies have suggested that MLPA results require implementing other detection methods due to false duplication. Our aim was to evaluate variables that could alter the peak ratio in MLPA in individuals with Duchenne/Becker muscular dystrophy (DMD/BMD) who present sequence variants at the probe hybridization site, such as the location of sequence variants (SVs), melting temperature of the probe, and the type of variant. Methods We analyzed patients with clinical suspicion of DMD/BMD through the MLPA technique. The DMD gene was sequenced in patients with normal results in MLPA. Results Of 111 patients, 72 had an abnormal MLPA result, of which 10 had a single exon abnormal peak, and 39 had a normal peak ratio. Out of 10 patients, 4 (40%) with a single exon abnormal peak ratio had SV at the hybridization site of the probe. In the other 6, the deletion was confirmed. Out of 39 patients with a normal peak ratio, 11 presented SVs at the hybridization site of the probe, and DMD/BMD was confirmed. Conclusions In cases of abnormal peak ratio results of MLPA in a single exon, it would be valuable to sequence the DMD gene to assess whether variants in the probe hybridization site might result in a false positive that could be interpreted as an exon deletion.

Antecedentes: Los trastornos del desarrollo sexual (TDS) incluyen un grupo de entidades clínicas infrecuentes. La baja prevalencia de estas enfermedades y el impacto social que tienen en la comunidad requieren el registro sistemático de la información clínica de los pacientes. Objetivo: caracterizar el espectro clínico de los casos de trastornos del desarrollo sexual diferentes al síndrome de Turner y Klinefelter valorados en el Hospital Universitario San Ignacio. Métodos: por cada caso se diligenció un formulario electrónico diseñado en la herramienta RedCap®, las variables consideradas para el registro se escogieron siguiendo las recomendaciones del Registro Internacional de Desórdenes de Diferenciación sexual (I-DSD). Resultados: se incluyeron en total 28 pacientes, 2 fueron diagnosticados con un tipo de trastorno de los cromosomas sexuales, 17 fueron diagnosticados con un tipo de trastorno del desarrollo sexual 46,XY y 9 con algún tipo de trastorno del desarrollo sexual 46,XX. Diferentes pruebas moleculares fueron solicitadas en el 96,4% de casos, logrando definir un diagnóstico etiológico en 7/28 de los casos. Conclusiones: nuestros hallazgos resaltan la importancia de los estudios citogenéticos como pruebas de primera línea en el enfoque diagnóstico de pacientes con TDS. Este trabajo es el inicio del primer registro de trastornos del desarrollo sexual no solo institucional sino nacional y muy seguramente aportará bases académicas para la construcción y ejecución de futuras investigaciones que permitan generar recomendaciones basadas en la evidencia para mejorar la atención clínica de los individuos afectados con algún tipo de TDS

Objectives: Etiology of gonadal dysgenesis and ovotesticular syndrome is unknown in a majority of cases. To perform cytogenetic and molecular characterization of a group of patients with ovotesticular syndrome and complete gonadal dysgenesis from peripheral blood and gonadal tissue samples. Materials and methods: A total of 6 patients were included, 3 with diagnosis of 46,XX ovotesticular syndrome, one diagnosed with 46,XY ovotesticular syndrome; one with suspected 46,XX gonadal dysgenesis, and one with 46,XY complete gonadal dysgenesis. Results: All patients were evaluated with karyotype, fluorescent in situ hybridization (FISH) for SRY, multiplex ligation-dependent probe amplification (MLPA) and comparative genomic hybridization (aCGH) on peripheral blood samples. In cases with available gonadal tissue, the levels of genetic expression of SOX3, SRY, and SOX9 were determined through real-time PCR and immunofluorescence. Rearrangements involving SRY gene were ruled out. No deletions/duplications or copy-number variations (CNV) were detected as the etiology for sexual development disorder in any of the patients studied. In a case of 46,XX ovotesticular syndrome, the gonadal karyotype was different from the karyotype in peripheral blood. Aberrant expression of SOX3 and SOX9 in gonadal tissue of a case with 46,XX ovotesticular syndrome was observed. Conclusions: Lower levels of expression of SRY and SOX9 compared to the levels in human cellular lines of embryonic testicle and Sertoli were documented in the gonadal tissue of a case with 46,XY ovotesticular syndrome. Cytogenetic and molecular studies of the gonads as a complement to peripheral blood study have the potential to enrich the understanding of sexual development disorders in patients who are XX or XY in peripheral blood.

The genetic basis for sporadic immunodeficiency in patients with 22q11.2 distal deletion syndrome is unknown. We report an adult with a type 1 (D-F) 22q11.2 distal deletion syndrome and recurrent severe infections due to herpes zoster virus, presenting mild T cell lymphopenia and diminished frequency of naive CD4+ T cells, but increased frequencies of central, effector, and terminally differentiated memory T cells. Antigen-specific CD4+ and CD8+ T cells to influenza, rotavirus, and SEB were conserved in the patient, but responses to tetanus toxoid were temporarily undetectable. Exomic sequencing identified the c.20_22dupCGG (NM_002745.4) variant in the remaining MAPK1 gene of the patient, which adds 1 alanine to the polyalanine amino-terminal tract of the protein (p.Ala7dup). The mother, unlike the father, was heterozygote for the variant. Western blot analysis with the patient's activated PBMCs showed a 91% reduction in the MAPK1 protein. Further studies will be necessary to determine whether or not the variant present in the remaining MAPK1 gene of the patient is pathogenic.

The anti-Müllerian hormone triggers the regression of uterus and fallopian tubes in male embryos; if there are problems in the synthesis or action of this protein, Müllerian structures persist in an otherwise phenotypic male. The most frequent clinical presentation of Persistent Mullerian Duct syndrome is cryptorchidism and inguinal hernia. The few cases reported in adults are incidental findings or inguinal hernias. However, we present an adult male with history of bilateral cryptorchidism with unsuccessful orchidopexy, who presents with a large abdominal mass with the finding of a seminomatous tumor and persistence of Müllerian structures, in whom the variant c.916delC (p.Leu306Cysfs*29) in the AMHR2 gene not previously reported was documented.

Disorders of sex development (DSDs) are congenital conditions in which the external appearance of the individual does not coincide with the chromosomal constitution or the gonadal sex. In other words, there is an ambiguous or intermediate condition between the male and female phenotypes of the anatomical sex. These atypical conditions are manifested in several ways, ranging from genital ambiguity to phenotypes that are so attenuated that they can go unnoticed or appear normal. Currently, there is a lack of understanding of the factors responsible for these outcomes; however, they are likely to be conditioned by genetic, hormonal and environmental factors during prenatal and postnatal development. The present study determined the genetic etiology of DSDs in Colombian patients by conventional cytogenetic analysis, FISH and MLPA (for SF1, DAX1, SOX9, SRY and WNT4). A cohort of 43 patients with clinical phenotypes of sex development disorder was used in the present study. Using this multistep experimental approach, a diagnostic percentage of 25.58% was obtained: 17 patients (39.53%) were classified as having gonadal development disorders, the majority of which were ovotesticular disorders with numerical and/or structural alterations of the sex chromosomes, 9 patients (20.93%) were classified as having testicular DSD with a 46,XY karyotype, and 3 patients (6.98%) as having ovarian DSD with a 46,XX karyotype. The remaining 14 patients (32.56%) were classified as ‘other’ since they could not be grouped into a specific class of gonadal development, corresponding to hypospadias and multiple congenital anomalies. These findings highlight the importance of histological and cytogenetic studies in a gonadal biopsy. In 11/43 cases, the multistep experimental protocol presented in the present study yielded etiological or histological findings that could be used to define the medical management of patients with DSDs. In conclusion, for the etiological diagnosis of DSDs, a broad-spectrum approach that includes endocrinological tests, conventional karyotyping, molecular karyotyping by FISH and, molecular tests is required, in addition to gonadal tissue analyses, to identify genetic alterations.

Muenke syndrome (MS) is the most common syndromic form of craniosynostosis with an incidence of 1 in 30,000 births, it corresponds to 8 percent of all craniosynostosis.1, 2 We report a data of a 5-year-old male patient with syndromic craniosynostosis and his father. Clinical view of patient and his father is analyzed. The 3D computed tomography scans are also discussed. A single surgery has been performed as a treatment for coronal craniosynostosis with bilateral frontoorbital advancement with bone grafts.

Isodicentric Y chromosome [idic(Y)] is one of the most common structural abnormalities of the Y chromosome and has been observed in patients with reproductive disorders and in patients with disorders of sexual development. Most idic(Y) chromosomes are found in mosaic form with a 45,X cell line. These chromosomes are highly unstable during mitosis due to the presence of 2 centromers, which explains their probable loss in early mitosis or mitosis of the embryo and therefore the presence of the 45,X line. It has been hypothesized that the proportion of 45,X cells in various tissues probably influences the phenotypic sex of individuals carrying an idic(Y) chromosome, ranging from infertile men, hypospadias, ambiguous genitalia, and Turner syndrome to sex reversal. In this article we present 5 cases of patients with idic(Y) referred for suspected disorder of sex development (DSD), 3 with a male assignment and 2 with a female assignment. All cases have variable clinical characteristics, which were assessed by the transdisciplinary group of Disorders of Sex Development of the Hospital Universitario San Ignacio, Bogotá, Colombia. Patients were analyzed by conventional and molecular cytogenetics using high-resolution G-band and FISH techniques. Our findings highlight the importance of cytogenetic studies in the diagnosis of DSD patients.

Resumen Introduccion La distrofia muscular de Duchenne (OMIM: 310200, ORPHA: 98896) es una miopatia hereditaria, recesiva, ligada a X. Es el desorden neuromuscular de etiologia genetica mas frecuente, con una incidencia de uno por cada 3.500 hombres y una prevalencia global de 4,78 por cada 100.000 personas. Metodos Se llevo a cabo una evaluacion clinica de 63 pacientes con distrofia muscular de Duchenne en un centro de referencia de Colombia. Se realizo a todos los sujetos un analisis molecular a traves de MLPA y una secuenciacion masiva en paralelo. Resultados En 47 de los 62 sujetos (75%) se detectaron variantes tipo delecion/duplicacion de exones en el gen de la distrofina, mediante MLPA. Se encontraron 33 probandos con deleciones (53,2%) y 14 casos de duplicaciones (22,5%) de uno o mas exones. El estudio de secuenciacion del gen DMD por la tecnica de secuenciacion masiva en paralelo fue realizado en 15 individuos (24,2%) con MLPA negativo. Se evidenciaron mutaciones sin sentido (nonsense) en 6 casos (9,6%), mutaciones que afectan el marco de lectura en 7 casos (11%) y mutaciones que afectan el splicing en 2 probandos (3,2%). No se encontraron mutaciones missense. Las variantes se distribuyeron a lo largo del gen y se encontraron 5 variantes que no habian sido previamente reportadas, identificadas en 7 individuos. Conclusiones El diagnostico molecular de mutaciones puntuales a traves de secuenciacion masiva paralela permitio alcanzar de manera eficiente la confirmacion diagnostica, definiendo para los casos negativos para delecion/duplicacion, la asesoria adecuada y la implementacion de un manejo terapeutico apropiado.

Disorders of sexual development (DSD) are conditions with an atypical chromosomal, gonadal or phenotypic sex, which leads to differences in the development of the urogenital tract and different clinical phenotypes. Some genes have been implicated in the sex development during gonadal and functional differentiation where the maintenance of the somatic sex of the gonad as either male or female is achieved by suppression of the alternate route. The diagnosis of DSD requires a structured approach, involving a multidisciplinary team and different molecular techniques. We discuss the dimorphic genes and the specific pathways involved in gonadal differentiation, as well as new techniques for genetic analysis and their diagnostic value including epigenetic mechanisms, expanding the evidence in the diagnostic approach of individuals with DSD to increase knowledge of the etiology.

Xia-Gibbs syndrome is an autosomal dominant multisystem developmental disorder characterized by global developmental delay, hypotonia, obstructive sleep apnea, seizures, retrocerebellar cysts, delayed myelination, micrognathia, and mild dysmorphic features. Using whole-exome sequencing, we identified a de novo AHDC1 frameshift mutation c.2030_2030delG (p.G677Afs*52) in a Colombian patient, which was absent in both parents. Furthermore, we summarized the phenotypes of patients reported in the literature.

Two sisters phenotypically normal females, presenting with tumor abdominal mass with histopathological findings of teratoma and gonadoblastoma associated to 46,XY male-to-female sex reversal syndrome, secondary to a duplication in DAX-1, possibly inherited of maternal gonadal mosaicism. Copy number variation and functional effects of the duplication were done by MLPA multiplex ligation-dependent probe amplification and real time PCR. DAX-1, also known as dosage sensitive sex reversal gene (DSS), is considered the most likely candidate gene involved in XY gonadal dysgenesis when overexpressed. The excess of DAX-1 gene disturbs testicular development by down regulation of SF-1, WT1, and SOX9. This is the first report of 46,XY sex reversal in two siblings who have a maternally inherited duplication of DAX-1 associated with reduced levels of expression of downstream genes as SOX9–SF1.

Xia-Gibbs syndrome is an autosomal dominant multisystem developmental disorder characterized by global developmental delay, hypotonia, obstructive sleep apnea, seizures, retrocerebellar cysts, delayed myelination, micrognathia, and mild dysmorphic features. Using whole-exome sequencing, we identified a de novo AHDC1 frameshift mutation c.2030_2030delG (p.G677Afs*52) in a Colombian patient, which was absent in both parents. Furthermore, we summarized the phenotypes of patients reported in the literature.

Introducción: las anomalías congénitas son una alteración estructural o funcional con impacto en la morbilidad-mortalidad infantil y la discapacidad mundial. Las estrategias orientadas a disminuir su impacto las respaldan sistemas de vigilancia. En Colombia, desde el 2010 se incluyó el formato de notificación de anomalías congénitas en el Sistema de Vigilancia (Sivigila). Objetivo: caracterizar epidemiológicamente la notificación del evento desde su inclusión. Materiales y métodos: análisis descriptivo de los eventos notificados entre enero de 2010 y diciembre de 2013. Resultados: se encontró una prevalencia de malformaciones del 0,35 % en Colombia durante el periodo analizado. Las anomalías congénitas con mayor notificación fueron las del sistema nervioso central y las anomalías de extremidades. Conclusiones: la prevalencia notificada para malformaciones congénitas en Colombia es baja. La baja tasa de notificación de anomalías congénitas evidencia la necesidad de realizar capacitaciones para mejorar esta notificación, tener un registro más cercano a la realidad de la población y así poder tomar decisiones para el beneficio de la población y en la generación de conocimiento en este tema.

Actualmente existe gran cantidad de información relacionada con el estrés y sus efectos. Por eso, este artículo se enfoca en el efecto de las hormonas del estrés en diversas áreas cerebrales, como lo son estructuras límbicas y en el eje hipotálamo-hipófisis-adrenal. Así mismo, se discutirá cómo el estrés repetitivo lleva a modificaciones en dichas áreas por el efecto de los glucocorticoides, pues dichas hormonas alteran la actividad basal de la amígdala, del hipocampo y de la corteza prefrontal medial, la función del eje hipotálamo-hipófisis-adrenal y funciones cognitivas como la memoria. Sin embargo, el mecanismo mediante el cual se producen dichos cambios es poco comprendido. Por eso, un reto a futuro es ligar los cambios celulares con sus efectos comportamentales, con el fin de entender su relación con el organismo in vivo.

Actualmente existe gran cantidad de información relacionada con el estrés y sus efectos. Por eso, este artículo se enfoca en el efecto de las hormonas del estrés en diversas áreas cerebrales, como lo son estructuras límbicas y en el eje hipotálamo-hipófisis-adrenal. Así mismo, se discutirá cómo el estrés repetitivo lleva a modificaciones en dichas áreas por el efecto de los glucocorticoides, pues dichas hormonas alteran la actividad basal de la amígdala, del hipocampo y de la corteza prefrontal medial, la función del eje hipotálamo-hipófisis-adrenal y funciones cognitivas como la memoria. Sin embargo, el mecanismo mediante el cual se producen dichos cambios es poco comprendido. Por eso, un reto a futuro es ligar los cambios celulares con sus efectos comportamentales, con el fin de entender su relación con el organismo in vivo.

Introducción. La apendicitis aguda es una de las principales causas de dolor abdominal y es la indicación quirúrgica más común por abdomen agudo. Existen pocos estudios sobre apendicitis en la población latinoamericana. Objetivo. Evaluar la frecuencia de los hallazgos histopatológicos de la apendicitis en una población de Boyacá (Colombia) y, con mayor detalle, los de apendicitis gangrenosa. Materiales y métodos. Se trata de un estudio descriptivo retrospectivo de los especímenes de apendicitis aguda de la base de datos del Departamento de Patología del Hospital San Rafael de Tunja, durante el periodo de enero a diciembre de 2011. Además, se revisaron de forma retrospectiva las historias clínicas de los pacientes con apendicitis gangrenosa. Resultados. Se encontraron 1.688 informes de histopatología de apendicitis aguda. Las muestras de tejidos provenían de siete áreas diferentes del departamento de Boyacá. Los estadios, por orden de frecuencia, fueron: apendicitis supurativa aguda (49 %), gangrenosa (24 %), apéndice normal (18 %) y apéndice edematoso (7 %). Otros diagnósticos histopatológicos (1 % del total de la muestra) fueron linfoma de Hodgkin, endometriosis, neuroma, tuberculosis apendicular, adenocarcinoma apendicular y tumores neuroendocrinos en el apéndice. Discusión. Se encontró que en la población boyacense, la apendicitis supurativa fue la presentación más frecuente, seguida de la gangrenosa. El diagnóstico de apendicitis gangrenosa mediante el examen físico, representa un reto para el médico. Este es el primer estudio en que se analiza una muestra de diagnósticos histopatológicos de apendicitis a nivel departamental en Colombia.