Development of Kompetitive Allele Specific PCR markers for identification of persimmon varieties using genotyping-by-sequencing

BACKGROUND: Persimmon (Diospyros kaki Thunb.) is the most widely cultivated species of the genus Diospyros. In this study, genetic diversity and variations in persimmon genotypes were investigated using single nucleotide polymorphism (SNP) markers identified by genotyping-by-sequencing (GBS) analysis. RESULTS: Ninety-five persimmon accessions grown in the Pear Research Institute, National Institute Horticultural and Herbal Science, were sequenced using the Illumina Hiseq2500 platform and polymorphic SNPs were detected to develop molecular markers. These reliable SNPs were analyzed using the Kompetitive Allele Specific PCR (KASP) assay to discriminate among persimmon genotypes. GBS generated a total of 447,495,724 trimmed reads, of which 89.7% were raw reads. After demultiplexing and sequence quality trimming, 108,876,644 clean reads were mapped to the reference transcriptome. An average of 1,146,070 genotype reads were mapped. Filtering of raw SNPs in each sample led to selection of a total of 1,725,401 high-quality SNPs. The number of homozygous and heterozygous SNPs ranged from 1,933 to 6,834 and from 846 to 5,927, respectively. CONCLUSIONS: Of the 49 SNPs selected for development of an identification system for persimmons, 15 SNPs were used in the KASP assay to analyze 32 persimmon accessions. These KASP markers discriminated among all accessions.

Trombosis senovenosa cerebral en un recién nacido con mutación MTHFR C677T tratado con enoxaparina / Cerebral sinovenous thrombosis in a newborn with mutation of MTHFR C677T treated with enoxaparin

Resumen: Introducción: La trombosis senovenosa cerebral neonatal (TSVC), es una patología rara y generalmente grave, de la cual se conoce poco sobre los mecanismos fisiopatológicos responsables y, aunque controvertido, se ha sugerido que la trombofilia genética, puede desempeñar un rol en la patogénesis. Debido a los temores de un sangrado intracraneal el tratamiento anticoagulante con heparina de bajo peso mole cular es controvertido. Objetivo: presentar un recién nacido con una trombosis senovenosa cerebral neonatal, discutir los factores de riesgo trombofílico, y el manejo con heparina de bajo peso molecu lar de la trombosis venosa cerebral. Caso Clínico: Recién nacido de término que debutó a los 8 días de vida con convulsiones clónicas, rechazo al pecho más hipoactividad motora. La neuroimagen con RM mostró una TSVC involucrando múltiples senos venosos, un infarto hemorrágico talámico dere cho y congestión venosa de la sustancia blanca frontal. El estudio de trombofilia puso de relieve una mutación homocigota del gen MTHFR C677T. El tratamiento con heparina de bajo peso molecular se asoció a repermeabilización del seno sagital superior a los 23 días de iniciada la terapia. Conclusio nes: La presentación clínica de la TSVC en el neonato es inespecífica, probablemente en relación con la extensión y gravedad de la lesión y el desarrollo de complicaciones asociadas, como infartos he morrágicos venosos intraparenquimatosos o hemorragia intraventricular. Estas complicaciones son detectables mediante Ecografia o Resonancia Magnética, y deben hacer sospechar una TSVC. En esta experiencia el tratamiento anticoagulante mostró ser seguro y prevenir la extensión de la trombosis.

Abstract: Introduction: Neonatal cerebral sinovenous thrombosis (CSNT) is a rare and generally serious con dition about which there is little knowledge of the responsible pathophysiological mechanisms and, although controversial, it has been suggested that genetic thrombophilia may play a role in its patho genesis. Out of concern for intracranial bleeding, the anticoagulant treatment with low-molecular- weight heparin is controversial. Objective: To present a case of a newborn with neonatal CSNT, to analyze the thrombophilic risk factors, and the management of cerebral venous thrombosis with low-molecular-weight heparin. Clinical Case: Full-term newborn who presented at eight days of life breastfeeding rejection, clonic seizures, and locomotor hypoactivity. The MRI neuroimaging showed a CSNT involving multiple venous sinuses, a right thalamic hemorrhagic infarction, and venous congestion in frontal white matter. Thrombophilia study highlighted a homozygous MTHFR C677T mutation. Treatment with low-molecular-weight heparin was associated with repermeabilization of the superior sagittal sinus after 23 days of starting therapy. Conclusions: The clinical presentation of CSNT in the neonate is nonspecific, probably related to the extent and severity of the injury and the development of associated complications, such as venous hemorrhagic infarctions and intraparenchymal or intraventricular hemorrhage. These complications are detected through ultrasound or MRI, and they should make us suspect a CSNT. In this experience, the anticoagulant treatment proved to be safe and prevents thrombus propagation.

Relationship between the polymorphism in the interleukin 1-β and the treatment time of patients subjected to a modified piezocision technique / Relación entre el polimorfismo en la interleucina 1-β y el tiempo de tratamiento de pacientes sometidos a una técnica de piezocisión modificada

Abstract Aim: We aimed to evaluate the correlation between the polymorphism of the interleukin 1-Beta (IL1-β, +3954 C>T) and tooth movement, in a group of Colombian patients undergoing surgically accelerated orthodontic tooth movement. Methods: The study was nested to a controlled clinical trial. Blood samples were taken from 11 women and 29 healthy Colombian male volunteers between 18 and 40 years old, after 1 year of starting orthodontic treatment. The patients presented malocclusion class I, with grade II or III. To detect the genetic polymorphism of the nucleotide +3954 C to T in the IL-1β gene, we used a real-time PCR assay. Results: Eleven individuals presented the allele 2 (T) heterozygous with the allele 1 (T/C) and 19 individuals were homozygous for the allele 1 (C/C). When analyzing the presence of the SNP, no significant differences were found in any of the variables. The best treatment was reflected in Group 3 (selective upper and lower alveolar decortication and 3D collagen matrix) and Group 4 (only selective alveolar decortication in the upper arch, with 3D collagen matrix), with 27% and 35% more speed respectively than in the control group. Conclusions: Our analyses indicated that a reduction in the total treatment time can be mostly potentiated by using decortication and collagen matrices and not for the presence of the allele 2 in the IL-1β. Nevertheless, it is important that further studies investigate if the polymorphism could be associated with the speed of tooth movement and analyze the baseline protein levels.

Resumen Objetivo: Evaluar la correlación entre el polimorfismo de la interleucina 1-Beta (IL1-β, +3954 C> T) y el movimiento de los dientes, en un grupo de pacientes colombianos sometidos a un movimiento dental ortodóncico acelerado quirúrgicamente. Métodos: Este fue un estudio secundario derivado de un ensayo clínico aleatorio controlado. Se tomaron muestras de sangre de 11 mujeres y 29 voluntarios varones colombianos sanos entre 18 y 40 años, después de 1 año de comenzar el tratamiento de ortodoncia. Los pacientes presentaron maloclusión clase I, con grado II o III. Para detectar el polimorfismo genético del nucleótido +3954 C a T en el gen IL-1β, se usó un ensayo de PCR en tiempo real. Resultados: 11 individuos presentaron el alelo 2 (T) heterocigoto con el alelo 1 (T / C) y 19 individuos fueron homocigotos para el alelo 1 (C / C). Al analizar la presencia del SNP, no se encontraron diferencias significativas en ninguna de las variables. El mejor tratamiento se reflejó en el Grupo 3 (decorticación alveolar superior e inferior selectiva y matriz de colágeno 3D) y el Grupo 4 (solo decorticación alveolar selectiva en el arco superior, con matriz de colágeno 3D), con un 27% y un 35% más de velocidad, respectivamente, que en el grupo de control. Conclusiones: Los análisis indicaron que una reducción en el tiempo total de tratamiento puede potenciarse principalmente mediante el uso de decorticación y matrices de colágeno y no por la presencia del alelo 2 en la IL-1β. Sin embargo, es importante que otros estudios investiguen si el polimorfismo podría estar asociado con la velocidad del movimiento de los dientes y analizar los niveles de proteína de referencia.

Novel homozygous mutation in a colombian patient with persistent müllerian duct syndrome: expanded phenotype

ABSTRACT 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.

Variante patogénica homocigótica del gen BBS10 en un paciente con síndrome de Bardet-Biedl / A pathogenic homozygous variant of the BBS10 gene in a patient with Bardet Biedl syndrome

Resumen El síndrome de Bardet-Biedl es una enfermedad hereditaria, autosómica recesiva, con gran heterogeneidad de locus, que pertenece a las denominadas ciliopatías, denominadas así por la deficiencia funcional presente y porque las proteínas afectadas se localizan en el cilio primario. El síndrome afecta múltiples sistemas, con compromiso visual, renal, cognitivo, esquelético y gonadal, y obesidad. Este síndrome presenta una gran variabilidad intrafamiliar e interfamiliar. Se presenta el caso clínico de un paciente adolescente con diagnóstico de síndrome de Bardet-Biedl, así como su manejo, los resultados de la secuenciación de 22 genes y el análisis actualizado de la literatura médica. Se recopiló la información clínica y, previo consentimiento informado, se hizo la prueba de panel de secuenciación multigénica de los genes implicados. El paciente es hijo de la unión de personas consanguíneas. Fue el primer afectado en la familia y presentaba polidactilia posaxial, obesidad, micropene, retinitis pigmentaria y dificultades de aprendizaje. En el panel multigénico, se identificó la variante patogénica homocigótica c.39_46del en el gen BBS10 y otras variantes de genes BBS asociadas con la obesidad. Dado que el síndrome de Bardet-Biedl es una enfermedad huérfana rara, interpretar el pleiotropismo y la heterogeneidad de locus y de alelos, constituye un reto. La confirmación molecular permite el manejo adecuado de los pacientes, así como el seguimiento y el asesoramiento genético apropiados.

Abstract The Bardet-Biedl syndrome is an autosomal recessive hereditary disorder with vast locus heterogeneity that belongs to the so-called ciliopathies, whose proteins are localized in the primary cilia and present functional deficiency. The multisystemic features of the disease include ocular, renal, cognitive, skeletal, as well as gonadal involvement and obesity, among others, with high inter- and intrafamilial variability. We describe the clinical case of an adolescent male patient with Bardet-Biedl syndrome, including the approach, the results from a 22-gene sequencing panel, and the analysis of updated scientific literature. We collected the clinical data of the patient and, after obtaining the informed consent, we conducted a multigenic sequencing panel oriented to known implicated genes. The patient was born to consanguineous parents and was the first affected member of the family. He presented with postaxial polydactyly, obesity, micropenis, retinitis pigmentosa, and learning disability. The multigenic panel allowed the identification of the homozygous pathogenic variant c.39_46del in the BBS10 gene and in other BBS genes variants associated with obesity. As the Bardet-Biedl syndrome is a rare disease, it is challenging to interpret its pleiotropism and gene/allelic heterogeneity. Its confirmation by molecular tests allows an adequate approach, follow-up, and genetic counseling of the patient and the family.

Variantes genéticas de la tiopurina metiltransferasa e incidencia de eventos adversos en pacientes con indicación de azatioprina / Genetic polymorphisms of thiopurine methyltransferase and incidence of adverse events in patients with medical indication of azathioprine

La azatioprina es una tiopurina que presenta rango terapéutico estrecho y marcada toxicidad hematológica y hepática. La tiopurina S-metiltransferasa es una enzima que metaboliza ese grupo de drogas. Mutaciones en el gen que codifica dicha enzima aumentan el riesgo de presentar eventos adversos, por lo que su estudio farmacogenético permite contar con información para el diseño de la estrategia terapéutica. Sin embargo, su utilidad en el medio local no está completamente establecida. Fueron incluidos 45 sujetos (13 hombres) con indicación de azatioprina. Se determinó la presencia de las mutaciones *2, *3A, *3B y *3C de TMPT por PCR-RFLP y se analizó la relación entre el genotipo y la incidencia de eventos adversos relacionados al fármaco. Nueve portaban al menos un alelo no funcional, uno de ellos con genotipo *3A/*3A. Se detectó toxicidad en 3 de los 18 que iniciaron tratamiento con azatioprina: 2 pacientes con genotipo normal presentaron eventos adversos leves, y el único evento adverso de gravedad (aplasia medular) ocurrió en el sujeto con genotipo homocigota mutado. El único que presentó genotipo homocigota mutado desarrolló el más grave de los eventos adversos registrados, a pesar de estar en tratamiento con dosis bajas de azatioprina. Por este motivo, la determinación del genotipo de la tiopurina metiltransferasa pareciera ser de utilidad, pero no reemplaza la necesidad de seguimiento clínico y bioquímico en pacientes en tratamiento con tiopurinas.

Azathioprine is a thiopurine which has a narrow therapeutic index and marked hematological and hepatic toxicity. Thiopurine s-methyltransferase is an enzyme involved in the metabolism of thiopurines. Mutations in the gene that encodes the enzyme may augment the risk of adverse events. For that reason, pharmacogenetic determinations prior to the initiation of therapy can provide useful information for the future therapeutic strategy. Nevertheless, its utility in the local environment is not completely established. Forty-five subjects (13 men) who had been prescribed azathioprine were included. The presence of *2, *3A, *3B and *3C mutations were determined by PCR-RFLP, and the relationship between genotype and incidence of adverse events related to the drug was analyzed. Nine carried at least one non-functional allele, one of them with *3A/*3A genotype. Among the eighteen patients who initiated treatment with azathioprine, toxicity was detected in 3 cases: 2 mild events were observed in patients with normal genotype, and the only serious event (bone marrow suppression) occurred in the individual with homozygous mutant genotype. The only homozygous mutant patient developed the most severe of the registered events, in spite of being under treatment with low doses of azathioprine. This is the reason why enzymatic determination could be of utility, even though it does not replace clinical and biochemical follow-up in patients under thiopurine treatment.

Simplified methodology for large scale isolation of homozygous transgenic lines of lettuce

Background: Lettuce is a globally important leafy vegetable and a model plant for biotechnology due to its adaptability to tissue culture and stable genetic transformation. Lettuce is also crucial for functional genomics research in the Asteraceae which includes species of great agronomical importance. The development of transgenic events implies the production of a large number of shoots that must be differentiated between transgenic and non-transgenic through the activity of the selective agent, being kanamycin the most popular. Results: In this work we adjusted the selection conditions of transgenic seedlings to avoid any escapes, finding that threshold concentration of kanamycin was 75 mg/L. To monitor the selection system, we studied the morphological response of transgenic and non-transgenic seedlings in presence of kanamycin to look for a visual morphological marker. Several traits like shoot length, primary root length, number of leaves, fresh weight, and appearance of the aerial part and development of lateral roots were affected in non-transgenic seedlings after 30 d of culture in selective media. However, only lateral root development showed an early, qualitative and reliable association with nptII presence, as corroborated by PCR detection. Applied in successive transgenic progenies, this method of selection combined with morphological follow-up allowed selecting the homozygous presence of nptII gene in 100% of the analyzed plants from T2 to T5. Conclusions: This protocol allows a simplified scaling-up of the production of multiple homozygous transgenic progeny lines in the early generations avoiding expensive and time-consuming molecular assays.

Variantes moleculares en el gen PARK2 en pacientes colombianos con enfermedad de Parkinson. Estudio piloto entre el 2013 y 2014 / Molecular variants in gene PARK2 in Colombian patients with Parkinson's disease. Pilot study between 2013 and 2014

Resumen Introducción: La enfermedad de Parkinson se caracteriza por la degeneración y pérdida de las neuronas dopaminérgicas en el cerebro. Existen factores genéticos involucrados en su desarrollo, en su forma de inicio temprano como el gen PARK2, codificante de la parkina, una E3 ubiquitín ligasa, lo que hace que en caso de mutaciones pierda su capacidad reguladora de degradación de proteínas causando estrés y muerte celular. Objetivo: Determinar la presencia de cambios moleculares en los exones 3, 4, y 5 de PARK2 en un grupo de 29 pacientes y 21 controles colombianos con enfermedad de Parkinson de inicio temprano o con antecedentes familiares de ella y la posible correlación con las manifestaciones clínicas de los pacientes. Materiales y métodos: Estudio descriptivo observacional (entre junio de 2013 y noviembre de 2014) en donde se realizó extracción de ADN de sangre total y se utilizó la técnica de PCR para cada uno de los exones. Finalmente se procedió a la secuenciación automática, análisis de las secuencias con el software Sequencher y comparación con información de bases de datos. Resultados: Se identificó una variante en estado homocigoto (Ala46Thr) en el exón 4 en un paciente no reportada anteriormente, posiblemente no patogénica y la variante Ser167Asn en estado heterocigoto en el mismo exón en otro paciente, considerada patogénica y reportada con anterioridad en poblaciones asiática y europea. No se identificaron variantes en los controles. Conclusiones: Los cambios no descritos antes en la población colombiana, -Ala46Thr y Ser167Asn-, fueron identificados en el grupo de pacientes. MÉD.UIS. 2017;30(3):31-8.

Abstract Introduction: Parkinson's disease is characterized by the degeneration and loss of dopaminergic neurons in the brain. There are genetic factors involved in its development in its early onset form, such as the PARK2 gene encoding the parkin, an E3 ubiquitin ligase, which in the case of mutations loses its ability to regulate protein degradation causing stress and cell death. Objective: To determine the presence of molecular changes in PARK2 exons 3, 4 and 5 in a group of 29 patients and 21 colombian controls with early onset Parkinson's disease or a family history of Parkinson's disease and the possible correlation with clinical manifestations from the patients. Materials and methods: Observational descriptive study (between june of 2013 and november of 2014) where DNA extraction of whole blood was performed and the PCR technique was used for each of the exons. Finally, we proceeded to the automatic sequencing, analysis of the sequences with the Sequencher software and comparison with information of databases. Results: A homozygous variant (Ala46Thr) in exon 4 was identified in one patient not previously reported, possibly nonpathogenic and the Ser167Asn variant in heterozygous state in the same exon in another patient, considered pathogenic and previously reported in populations Asian and European. No variants were identified in the controls. Conclusions: changes not previously described in the colombian population, -Ala46Thr and Ser167Asn-, were identified in the group of patients and not in the controls. MÉD.UIS. 2017;30(3):31-8.

A novel homozygous mutation in the solute carrier family 12 member 3 gene in a Chinese family with Gitelman syndrome

Loss of function of mutated solute carrier family 12 member 3 (SLC12A3) gene is the most frequent etiology for Gitelman syndrome (GS), which is mainly manifested by hypokalemia, hypomagnesemia and hypocalciuria. We report the genetic characteristics of one suspicious Chinese GS pedigree by gene sequencing. Complete sequencing analysis of the SLC12A3 gene revealed that both the proband and his elder sister had a novel homozygous SLC12A3 mutation: c.2099T>C and p.Leu700Pro. Moreover, the SLC12A3 genes of his mother and daughter encoded the same mutated heterozygote. It was noted that in this pedigree, only the proband complained about recurrent episodes of bilateral lower limb weakness over 8 years, while his elder sister, mother and daughter did not present symptoms. The inconsistent clinical features of this pedigree implied that besides diverse phenotypes possibly originated from the same genotype, gender difference may also dominate the variant GS phenotypes. Further genetic and proteomic research are needed to investigate the precise mechanisms of GS, including the study of specific ethnicities.

Charcot Marie Tooth disease (CMT4A) due to GDAP1 mutation: report of a colombian family / Enfermedad de Charcot Marie Tooth (CMT4A) por mutacion en el gen GDAP1: reporte de una familia colombiana

Background: Mutations of GDAP1 gene cause autosomal dominant and autosomal recessive Charcot-Marie-Tooth disease and more than 40 different mutations have been reported. The recessive Q163X mutation has been described in patients of Spanish ancestry, and a founder mutation in South American patients, originating in Spain has been demonstrated. Objective: We describe physical and histological features, and the molecular impact of mutation Q163X in a Colombian family. Methods: We report two female patients, daughters of consanguineous parents, with onset of symptoms within the first two years of life, developing severe functional impairment, without evidence of dysmorphic features, hoarseness or diaphragmatic paralysis. Electrophysiology tests showed a sensory and motor neuropathy with axonal pattern. Sequencing of GDAP1 gene was requested and the study identified a homozygous point mutation (c.487 C>T) in exon 4, resulting in a premature stop codon (p.Q163X). This result confirms the diagnosis of Charcot-Marie-Tooth disease, type 4A. Results: The patients were referred to Physical Medicine and Rehabilitation service, in order to be evaluated for ambulation assistance. They have been followed by Pulmonology service, for pulmonary function assessment and diaphragmatic paralysis evaluation. Genetic counseling was offered. The study of the genealogy of the patient, phenotypic features, and electrophysiological findings must be included as valuable tools in the clinical approach of the patient with Charcot-Marie-Tooth disease, in order to define a causative mutation. In patients of South American origin, the presence of GDAP1 gene mutations should be considered, especially the Q163X mutation, as the cause of CMT4A disease.

Antecedentes: Las mutaciones del gen GDAP1 son causantes de la enfermedad de Charcot Marie Tooth tanto autosómica dominante como recesiva, y se han reportado más de 40 mutaciones distintas. La mutación recesiva Q163X ha sido descrita en pacientes de ascendencia española y se ha demostrado una mutación fundadora originaria de España en pacientes de origen suramericano. Describimos las características físicas e histológicas y el impacto molecular de la mutación Q163X en una familia colombiana. Objetivo: Se describe el impacto de la mutación Q163X en las características físicas, histológicas y moleculares en una familia colombiana. Métodos: Se describe dos pacientes de sexo femenino, hijas de padres consanguíneos, quienes presentaron inicio de síntomas en los dos primeros años de vida, mostrando deterioro funcional severo, sin evidencia de dismorfía, disfonía o parálisis diafragmática. Los estudios de electrofisiología mostraron una neuropatía sensitiva y motora con patrón axonal. Se solicitó la secuenciación del gen GDAP1, y el estudio identificó una mutación homocigota puntual (c. 487 C>T) en el exón 4, causando un codón de parada prematuro (p. Q163X). Este resultado confirma el diagnóstico de Enfermedad de Charcot Marie Tooth, tipo 4A (recesiva, tipo axonal). Resultados: Las pacientes fueron remitidas al servicio de Fisiatría para evaluación de métodos de asistencia para deambulación. Ellas reciben seguimiento por el servicio de Neumología, quienes vigilan la función pulmonar y el desarrollo de parálisis diafragmática. Se brindó asesoramiento genético. La genealogía del paciente, las características fenotípicas y los hallazgos en los estudios electrofisiológicos son herramientas valiosas en el enfoque clínico del paciente con CMT, de forma que se pueda plantear una posible mutación causal. Se debe considerar la presencia de mutaciones en el gen GDAP1 en pacientes de origen suramericano, en especial la mutación Q163X, como causa de CMT4A.

Bases moleculares de alfa-talasemia en la Argentina

La α-talasemia, es uno de los desórdenes hereditarios más frecuentes mundialmente. Al presente, el diagnóstico molecular es la única herramienta que permite el diagnóstico certero. El propósito de este trabajo fue caracterizar las bases moleculares de estos síndromes en nuestro medio, y establecer relaciones genotipo-fenotipo. Mediante la complementación de distintas técnicas de biología molecular e hibridación fluorescente in situ (FISH), se logró poner en evidencia la presencia de mutaciones α-talasémicas en 145 de 184 (78.8%) pacientes estudiados con perfil hematológico compatible con α-talasemia. Dentro de este grupo, las deleciones correspondieron al defecto genético más frecuente, prevaleciendo la mutación -α3.7 en genotipos heterocigotas y homocigotas. Asimismo, en pacientes con fenotipo α0 las deleciones prevalentes fueron -MED y -CAL/CAMP. Este estudio permitió también describir una deleción de la región sub-telomérica en un paciente con α-talasemia y retraso mental. En el 7.6% de los pacientes caracterizados clínicamente como posibles α-talasémicos (microcitosis con valores de Hb A2 inferiores al 3.5%), se hallaron mutaciones β-talasémicas en estado heterocigota. Se lograron establecer perfiles hematológicos asociados a los genotipos α+ y α0 para pacientes adultos y niños. Esperamos que este trabajo pueda servir como guía para reconocer posibles portadores α-talasémicos. También permite destacar el trabajo en conjunto de médicos hematólogos, el laboratorio (bioquímico y de biología molecular) y de los médicos genetistas, con el fin de proporcionar adecuado consejo genético.

The α-thalassemia is one of the most common hereditary disorders worldwide. Currently, molecular diagnostics is the only available tool to achieve an accurate diagnosis. The purpose of this study was to characterize the molecular bases of these syndromes in our environment and to establish genotype-phenotype associations. Through a combination of different molecular techniques and fluorescent in situ hybridization (FISH),we were able to find α-thalassemic mutations in 145 of the 184 patients (78.8%) studied with hematological parameters compatible with α-thalassemia. Deletions of the a-globin genes resulted the major molecular cause of the disease, and the most frequent mutation was -α3.7, found in homozygous and heterozygous genotypes. In patients with α0 phenotypes, other prevalent mutations were -MED and -CAL/CAMP. The description of a sub-telomeric deletion in a patient with α-thalassemia and mental retardation was also achieved. β-thalassemic mutations in heterozygous state were found in 7.6% of the patients, who presented α-thalassemic clinical features (microcytosis and Hb A2 levels below 3.5%). Hematologic profiles for the α+ and α0 genotypes were established for adult and pediatric patients. Hopefully, this work will provide guidelines for the detection of possible α-thalassemic carriers. It also highlights the collaborative work of hematologists, the biochemical and molecular biology laboratory and genetists, in order to provide appropriate genetic counseling.

El síndrome de Pasqualini: hipoandrogenismo con espermatogénesis conservada

Pasqualini y Bur publican el primer caso de eunucoidismo con espermatogénesis conservada en 1950 en la Revista de la Asociación Médica Argentina. El síndrome de hipoandrogenismo con espermatogénesis incluye: (a) eunucoidismo bien definido, (b) testículos de volumen normal con espermatogénesis completa, llegando a espermatozoides maduros en una elevada proporción de tubos seminíferos, con células de Leydig indiferenciadas e inmaduras, (c) compensación funcional completa mediante la administración de gonadotrofina coriónica, mientras ésta se aplique (d) gonadotrofinas urinarias totales dentro de límites normales, y (e) esta definición fue ampliada con la actividad normal de las otras hormonas adenohipofisarias y la ausencia de malformaciones congénitas en la mayoría de los casos. En la fisiopatogenia del síndrome de Pasqualini, conocido también como síndrome del "eunuco fértil", se demostró primero la ausencia de hormona luteinizante (LH) en el plasma y orina de estos pacientes. El segundo gran avance fueron los estudios funcionales y genéticos que validaron la hipótesis de un déficit funcional de LH en estos hombres, extendido luego a las mujeres. Varios grupos, incluyendo el nuestro, demostrarían en estos casos una LH con diferentes grados de actividad inmunológica pero biológicamente inactiva, a partir de una o más mutaciones invalidantes en el gen LHB. Por último, la comprensión acabada del síndrome de Pasqualini permitiría revertir el fenotipo y la infertilidad de estos pacientes a partir de la utilización de gonadotrofina coriónica y las modernas técnicas de fertilidad in vitro. Este artículo es una revisión histórica y un homenaje a la memoria de Rodolfo Q. Pasqualini.

Pasqualini and Bur published the first case of eunuchoidism with preserved spermatogenesis in 1950 in Revista de la Asociación Médica Argentina. The hypoandrogenism with spermatogenesis syndrome included: (a) eunuchoidism, (b) testis with normal spermatogenesis and full volume, with mature spermatozoa in a high proportion of seminiferous tubes and undifferentiated and immature Leydig cells (c) full functional compensation through the administration of chorionic gonadotropin hormone, while hCG is administered (d) total urinary gonadotrophins within normal limits (e) this definition supposes the normal activity of the pituitary and the absence of congenital malformations in general. A first step in the understanding of the physiopathogeny of Pasqualini syndrome or the so called "fertile eunuch" syndrome was the absence of LH in plasma and urine of patients. The second breakthrough was the functional and genetic studies that validated the hypothesis of a functional deficit of LH in these men: it will then also be described in some women. Different groups including ours demonstrated in these cases a LH with varying degrees of immunological activity but biologically inactive in most of the patients, due to one or more inactivating mutations in the LHB gene. Finally, the full comprehension of Pasqualini syndrome allowed to reverse the hypoandrogenic phenotype and to restore fertility in these patients through the use of chorionic gonadotropin and the modern in-vitro fertility techniques. This article is an historical review and a tribute to the memory of Rodolfo Q. Pasqualini.

Tuberculosis in renal transplant patients: The experience of a single center in Medellín-Colombia, 2005-2013 / Tuberculose em pacientes transplantados renais: experiência de um único centro em Medellín-Colômbia, 2005-2013

Introduction: Tuberculosis is a common opportunistic infection in renal transplant patients. Objective: To obtain a clinical and laboratory description of transplant patients diagnosed with tuberculosis and their response to treatment during a period ranging from 2005 to 2013 at the Pablo Tobón Uribe Hospital. Methods: Retrospective and descriptive study. Results: In 641 renal transplants, tuberculosis was confirmed in 12 cases. Of these, 25% had a history of acute rejection, and 50% had creatinine levels greater than 1.5 mg/dl prior to infection. The disease typically presented as pulmonary (50%) and disseminated (33.3%). The first phase of treatment consisted of 3 months of HZRE (isoniazid, pyrazinamide, rifampicin and ethambutol) in 75% of the cases and HZME (isoniazid, pyrazinamide, moxifloxacin and ethambutol) in 25% of the cases. During the second phase of the treatment, 75% of the cases received isoniazid and rifampicin, and 25% of the cases received isoniazid and ethambutol. The length of treatment varied between 6 and 18 months. In 41.7% of patients, hepatotoxicity was associated with the beginning of anti-tuberculosis therapy. During a year-long follow-up, renal function remained stable, and the mortality rate was 16.7%. Conclusion: Tuberculosis in the renal transplant population studied caused diverse nonspecific symptoms. Pulmonary and disseminated tuberculosis were the most frequent forms and required prolonged treatment. Antituberculosis medications had a high toxicity and mortality. This infection must be considered when patients present with a febrile syndrome of unknown origin, especially during the first year after renal transplant. .

Introdução: A tuberculose é uma infecção oportunista comum em pacientes transplantados renais. Objetivo: Oferecer uma descrição clínica e laboratorial de pacientes transplantados com diagnóstico de tuberculose e sua resposta ao tratamento durante o período entre 2005 e 2013 no Hospital Pablo Tobón Uribe. Métodos: Estudo retrospectivo descritivo. Resultados: Em 641 transplantes renais, a tuberculose foi confirmada em 12 pacientes. Destes, 25% tinham histórico de rejeição aguda e 50% apresentaram níveis de creatinina superiores a 1,5 mg/dl antes da infecção. A patologia geralmente se apresentava como pulmonar (50%) e disseminada (33,3%). A primeira fase do tratamento consistiu de três meses de HZRE (isoniazida, pirazinamida, rifampicina e etambutol) em 75% dos casos e HZME (isoniazida, pirazinamida, moxifloxacina e etambutol) em 25% dos pacientes. Durante a segunda fase do tratamento, 75% dos pacientes receberam isoniazida e rifampicina e 25% isoniazida e etambutol. A duração do tratamento variou entre seis e 18 meses. Em 41,7% dos pacientes, hepatotoxicidade foi associada ao início do tratamento da tuberculose. Durante o seguimento de um ano a função renal manteve-se estável e a taxa de mortalidade foi de 16,7%. Conclusão: A tuberculose foi responsável por diversos sintomas inespecíficos na população de transplantados renais estudada. Tuberculose pulmonar e disseminada foram as formas mais frequentes de acometimento e necessitaram de tratamento prolongado. Medicamentos contra a tuberculose apresentaram alta toxicidade e mortalidade. Esta infecção deve ser considerada quando o paciente apresenta síndrome febril de origem desconhecida, especialmente durante o primeiro ano após o transplante renal. .

Sheep gastrointestinal helminthiasis in the Sertão region of Paraíba State, Northeastern Brazil: prevalence and risk factors / Helmintoses gastrintestinais de ovinos no Sertão do Estado da Paraíba, Nordeste do Brasil: prevalência e fatores de riscos

In this study, we aimed to establish the prevalence and risk factors relating to gastrointestinal helminthiasis, and to characterize the sanitary management practiced among sheep herds in the Sertão region of the state of Paraíba, northeastern Brazil, based on factors that condition the ways of controlling these parasites in these herds. The research was carried out between April and July 2012. We visited 54 farms, where fecal and blood samples were individually collected from 465 animals. On each farm, a questionnaire was applied to gather information on variables relating to potential risk factors. The prevalence of sheep gastrointestinal helminthiasis in the region was 75.9%. At least one animal tested positive for this helminthiasis on 53 (98.1%) of the 54 farms evaluated. The eggs per gram of feces (EPG) analysis showed the following infection burdens: 51.8% with mild infection, 27.1% moderate infection, 9.9% heavy infection and 11.2% fatal infection. Among the sheep farms visited, anthelmintics were used on 81.5% (p <0.05). The most relevant risk factor in this study was the farm area, because it defines the area available for grazing animals. Properties with many animals and little pasture area, which are the most abundant type in the Sertão region of Paraíba, tend to have high prevalence of gastrointestinal helminthiasis, because the animals are more prone to reinfection. The Sertão region of Paraíba presents high prevalence of gastrointestinal helminthiasis among sheep, and the farm area is the most relevant risk factor for the development of these parasites.

Objetivou-se determinar a prevalência e os fatores de risco para as helmintoses gastrintestinais, caracterizando o manejo sanitário sob fatores condicionantes das formas de controle dessas parasitoses em rebanhos de ovinos da região do Sertão da Paraíba. A pesquisa foi desenvolvida no período de abril a julho de 2012. Foram visitadas propriedades, utilizando-se 465 animais, sendo coletadas individualmente amostras de fezes e sangue durante as visitas. Em cada propriedade, foi aplicado questionário para a coleta de informações acerca de variáveis que atuariam como possíveis fatores de risco. Observou-se que a prevalência das helmintoses gastrintestinais de ovinos na região do Sertão da Paraíba foi de 75,9%. Pelo menos um animal foi positivo para essas helmintoses, em 53 (98,1%) das 54 propriedades avaliadas. A análise de OPG (Ovos Por Gramas de Fezes) demonstrou que 51,8% dos animais apresentaram infecção leve, 27,1% infecção moderada, 9,9% infecção pesada e 11,2% infecção fatal. A utilização de anti-helmínticos ocorreu em 81,5% das propriedades (p <0,05). O fator de risco mais relevante neste estudo foi a área da propriedade, porque delimita a área de pastejo do animal. Propriedades com muitos animais e pouca área de pastejo, que são as mais abundantes no Sertão da Paraíba, tendem a apresentar alta prevalência de helmintoses gastrintestinais, pois os animais estão mais propensos à reinfecção. A região do Sertão da Paraíba apresenta uma elevada prevalência de helmintoses gastrintestinais em ovinos, e a área das propriedades é o fator de risco mais relevante para o desenvolvimento dessas parasitoses.

3?-hydroxysteroid dehydrogenase type II deficiency on newborn screening test / Deficiência de 3?-hidroxiesteroide desidrogenase tipo 2 em teste de triagem neonatal

3b-hydroxysteroid dehydrogenase II (3β-HSD) deficiency represents a rare CAH variant. Newborns affected with its classic form have salt wasting in early infancy and genital ambiguity in both sexes. High levels of 17-hydroxypregnenolone (Δ517OHP) are characteristic, but extra-adrenal conversion to 17-hydroxyprogesterone (17OHP) may lead to positive results on newborn screening tests. Filter paper 17OHP on newborn screening test was performed by immunofluorometric assay, and serum determinations of 17OHP and Δ517OHP, by radioimmunoassay. A 46,XY infant with genital ambiguity and adrenal crisis at three months of age presented a positive result on newborn screening for CAH. Serum determinations of 17OHP and Δ517OHP were elevated, and a high Δ517OHP/cortisol relation was compatible with the diagnosis of 3β-HSD deficiency. Molecular analysis of the HSD3B2 gene from the affected case revealed the presence of the homozygous p.P222Q mutation, whereas his parents were heterozygous for it. We present the first report of 3β-HSD type II deficiency genotype-proven detected at the Newborn Screening Program in Brazil. The case described herein corroborates the strong genotype-phenotype correlation associated with the HSD3B2 p.P222Q mutation, which leads to a classic salt-wasting 3β-HSD deficiency. Further evaluation of 17OHP assays used in newborn screening tests would aid in determining their reproducibility, as well as the potential significance of moderately elevated 17OHP levels as an early indicator to the diagnosis of other forms of classic CAH, beyond 21-hydroxylase deficiency.

A deficiência da enzima 3β-hidroxiesteroide desidrogenase tipo 2 (3β-HSD) representa variante rara de hiperplasia adrenal congenital (HAC). Recém-nascidos afetados com a forma clássica apresentam perda de sal nas primeiras semanas de vida e ambiguidade genital em ambos os sexos. Concentrações elevadas de 17-hidroxipregnenolona (Δ517OHP) são características, porém sua conversão extra-adrenal a 17-hidroxiprogesterona (17OHP) pode resultar em resultados positivos no teste de triagem neonatal. A determinação da concentração de 17OHP obtida em amostra de sangue colhida em papel-filtro para triagem neonatal foi realizada por ensaio imunofluorimétrico, e as concentrações séricas de 17OHP and Δ517OHP, por radioimunoensaio. Um menino, 46,XY, com ambiguidade genital e crise adrenal aos 3 meses de vida, apresentou teste positivo na triagem neonatal para HAC. As concentrações séricas de 17OHP e Δ517OHP estavam aumentadas, bem como a relação Δ517OHP/cortisol, o que foi compatível com o diagnóstico de deficiência de 3β-HSD. A análise molecular do gene HSD3B2 revelou a mutação p.P222Q em homozigose na criança afetada e em heterozigose em seus pais, o que confirmou a deficiência de 3β-HSD com resultado moderadamente elevado na dosagem de 17OHP no “Teste do Pezinho” (Programa de Triagem Neonatal do Distrito Federal, Brasil). Esse caso corrobora a forte correlação genótipo-fenótipo associada à mutação p.P222Q no gene HSD3B2. Estudos futuros para avaliação dos ensaios utilizados na triagem neonatal para determinação de 17OHP poderão auxiliar na determinação do significado potencial de concentrações moderadamente elevadas de 17OHP como um indicador precoce para o diagnóstico de outras formas de HAC clássicas, além da deficiência de 21-hidroxilase.

Hipoplasia tímica en un niño con fibrosis quística / Thymic hypoplasia in an infant with cystic fibrosis

La fibrosis quística es la enfermedad autosómica recesiva más frecuente en poblaciones caucásicas; en Cuba, uno de cada 5 000 recién nacidos están afectados. En 1989 fue clonado el gen regulador de la conductancia transmembranal de la fibrosis quística e identificada su mutación principal, F508del. Desde entonces han sido descritas más de 1 300 mutaciones diferentes en este gen. El timo es el principal órgano de maduración de los linfocitos T, es relativamente grande y muy activo al nacer. El síndrome de Di George, descrito en 1965, incluye varias malformaciones congénitas y déficit inmunológico, principalmente de células T por hipoplasia del timo. Actualmente existen criterios definitivos, probables y posibles que diagnostican la entidad y se reportan síndromes completos y parciales en dependencia de los síntomas y signos presentes en el enfermo; sin embargo, puede observarse hipoplasia severa del timo en pacientes sin diagnóstico de Di George. Se presenta el caso de un paciente pediátrico en el que se define el diagnóstico de fibrosis quística por estudios moleculares y se identifica como homocigótico para la mutación F508del con hipoplasia severa del timo

Cystic fibrosis is the most common autosomal recessive disease in Caucasian populations; in Cuba, one in 5 000 newborns are affected. In 1989, the conductance regulator gene for cystic fibrosis transmembrane was cloned and its main mutation F508del was identified. Since then, over 1 300 different mutations in the gene have been described. The thymus is the primary organ of T cell maturation, is relatively large and very active at birth. DiGeorge syndrome, described in 1965, includes several birth defects and immune deficits, mainly of T cells by thymic hypoplasia. Currently, definitive, probable and possible criteria to diagnose the entity exist as well as reports of full and partial syndromes depending of symptoms present in the patient; nevertheless, severe thymic hypoplasia can be observed in patients without diagnosis of Di George. We report the case of a pediatric patient with diagnosis of cystic fibrosis by molecular studies identified as homozygous for the mutation F508del with severe thymic hypoplasia

Segregation distortion in homozygous lines obtained via anther culture and maize doubled haploid methods in comparison to single seed descent in wheat (Triticum aestivum L. )

Background The quality of wheat grain depends on several characteristics, among which the composition of high molecular weight glutenin subunits, encoded by Glu-1 loci, are the most important. Application of biotechnological tools to accelerate the attainment of homozygous lines may influence the proportion of segregated genotypes. The objective was to determine, whether the selection pressure generated by the methods based on in vitro cultures, may cause a loss of genotypes with desirable Glu-1 alleles. Results Homozygous lines were derived from six winter wheat crosses by pollination with maize (DH-MP), anther culture (DH-AC) and single seed descent (SSD) technique. Androgenetically-derived plants that originated from the same callus were examined before chromosome doubling using allele-specific and microsatellite markers. It was found that segregation distortion in SSD and DH-MP populations occurred only in one case, whereas in anther-derived lines they were observed in five out of six analyzed combinations. Conclusions Segregation distortion in DH-AC populations was caused by the development of more than one plant of the same genotype from one callus. This distortion was minimized if only one plant per callus was included in the population. Selection of haploid wheat plants before chromosome doubling based on allele-specific markers allows us to choose genotypes that possess desirable Glu-1 alleles and to reduce the number of plants in the next steps of DH production. The SSD technique appeared to be the most advantageous in terms of Mendelian segregation, thus the occurrence of residual heterozygosity can be minimized by continuous selfing beyond the F6 generation.

Robertsonian chromosomes and the nuclear architecture of mouse meiotic prophase spermatocytes

BACKGROUND: The nuclear architecture of meiotic prophase spermatocytes is based on higher-order patterns of spatial associations among chromosomal domains from different bivalents. The meiotic nuclear architecture depends on the chromosome characteristics and consequently is prone to modification by chromosomal rearrangements. In this work, we consider Mus domesticus spermatocytes with diploid chromosome number 2n = 40, all telocentric, and investigate a possible modification of the ancestral nuclear architecture due to the emergence of derived Rb chromosomes, which may be present in the homozygous or heterozygous condition. RESULTS: In the 2n = 40 spermatocyte nuclei random associations mediated by pericentromeric heterochromatin among the 19 telocentric bivalents ocurr at the nuclear periphery. The observed frequency of associations among them, made distinguishable by specific probes and FISH, seems to be the same for pairs that may or may not form Rb chromosomes. In the homozygote Rb 2n = 24 spermatocytes, associations also mediated by pericentromeric heterochromatin occur mainly between the three telocentric or the eight metacentric bivalents themselves. In heterozygote Rb 2n = 32 spermatocytes all heterochromatin is localized at the nuclear periphery, yet associations are mainly observed among the three telocentric bivalents and between the asynaptic axes of the trivalents. CONCLUSIONS: The Rb chromosomes pose sharp restrictions for interactions in the 2n = 24 and 2n = 32 spermatocytes, as compared to the ample possibilities for interactions between bivalents in the 2n = 40 spermatocytes. Undoubtedly the emergence of Rb chromosomes changes the ancestral nuclear architecture of 2n = 40 spermatocytes since they establish new types of interactions among chromosomal domains, particularly through centromeric and heterochromatic regions at the nuclear periphery among telocentric and at the nuclear center among Rb metacentric ones.

Trombocitopenia familiar de plaquetas gigantes: caso clínico / Familiar Thrombocytopenia of Giant Platelets: Clinical Case

La trombocitopenia es causa frecuente de consulta en hematología pediátrica. La mayoría de veces la baja de plaquetas es por desorden de destrucción autoinmune, raramente el padecimiento tiene un comportamiento familiar-hereditario. Se presenta el caso de una paciente de 11 años de edad, conocida desde los 3 años por trombocitopenia en el rango de 50,000/mm , fue evaluada por posibilidad de desórdenes autoinmunescon estudios inmunológicos básicos: complementos, ANA, Anti ADN, factor reumatoide y los resultados fueron normales. Tratada en varias ocasiones con prednisona oral, antiRh y con inmunoglobulina intravenosa (IGIV). Se le ha brindado seguimiento prolongado por trombocitopenia que resultó ser familiar; encontrando doce afectados, que incluyen abuela materna, madre, tíos, primos y hermana. Las características clínicas y la morfología plaquetaria fueron finalmente suficientes para conducir a diagnóstico inusual: el síndrome de Bernard-Soulier (SBS). El diagnóstico fue sugerido por el frotis de sangre periférica (FSP)...

Cystic fibrosis transmembrane conductance regulator mutations at a referral center for cystic fibrosis / Mutações no gene cystic fibrosis transmembrane conductance regulator em um centro de referência para a fibrose cística

OBJECTIVE: To determine the frequency of six mutations (F508del, G542X, G551D, R553X, R1162X, and N1303K) in patients with cystic fibrosis (CF) diagnosed, at a referral center, on the basis of abnormal results in two determinations of sweat sodium and chloride concentrations. METHODS: This was a cross-sectional study involving 70 patients with CF. The mean age of the patients was 12.38 ± 9.00 years, 51.43% were female, and 94.29% were White. Mutation screening was performed with polymerase chain reaction (for F508del), followed by enzymatic digestion (for other mutations). Clinical analysis was performed on the basis of gender, age, ethnicity, pulmonary/gastrointestinal symptoms, and Shwachman-Kulczycki (SK) score. RESULTS: All of the patients showed pulmonary symptoms, and 8 had no gastrointestinal symptoms. On the basis of the SK scores, CF was determined to be mild, moderate, and severe in 22 (42.3%), 17 (32.7%), and 13 (25.0%) of the patients, respectively. There was no association between F508del mutation and disease severity by SK score. Of the 140 alleles analyzed, F508del mutation was identified in 70 (50%). Other mutations (G542X, G551D, R553X, R1162X, and N1303K) were identified in 12 (7.93%) of the alleles studied. In F508del homozygous patients with severe disease, the OR was 0.124 (95% CI: 0.005-0.826). CONCLUSIONS: In 50% of the alleles studied, the molecular diagnosis of CF was confirmed by identifying a single mutation (F508del). If we consider the analysis of the six most common mutations in the Brazilian population (including F508del), the molecular diagnosis was confirmed in 58.57% of the alleles studied. .

OBJETIVO: Determinar a frequência de seis mutações (F508del, G542X, G551D, R553X, R1162X e N1303K) em pacientes com fibrose cística (FC) de um centro de referência, diagnosticados pela presença de duas dosagens de sódio e cloro no suor alteradas. MÉTODOS: Estudo de corte transversal com 70 pacientes com idade média de 12,38 ± 9,00 anos, sendo que 51,43% eram do sexo feminino, e 94,29% eram caucasoides. A triagem de mutações foi realizada pela técnica de reação em cadeia da polimerase (F508del), seguida por digestão enzimática (demais mutações). A análise clínica foi realizada utilizando as variáveis sexo, idade, etnia, manifestações pulmonares/digestivas e escore de Shwachman-Kulczycki (ESK). RESULTADOS: Todos os pacientes apresentaram manifestações pulmonares, e 8 não apresentaram manifestações digestivas. Os resultados do ESK evidenciaram doença leve, moderada e grave, respectivamente, em 22 (42,3%), 17 (32,7%) e 13 (25,0%) pacientes. Não houve associação da mutação F508del com o grau de doença pelo ESK. Dos 140 alelos analisados, a mutação F508del foi identificada em 70 (50%). As demais mutações (G542X, G551D, R553X, R1162X e N1303K) foram identificadas em 12 (7,93%) dos alelos analisados. Em pacientes homozigotos F508del com doença grave, a OR foi de 0,124 (IC95%: 0,005-0,826). CONCLUSÕES: O diagnóstico molecular de FC foi confirmado pela identificação de apenas uma mutação (F508del) em 50% dos alelos estudados. Se considerarmos a análise das seis mutações de maior frequência na população brasileira (incluindo F508del), o diagnóstico molecular foi confirmado em 58,57% dos alelos analisados. .