X-linked forms of retinitis pigmentosa (XLRP) are among the most severe because of their early onset, often leading to significant visual impairment before the fourth decade. RP3, genetically localized at Xp21.1, accounts for 70% of XLRP in different populations. The RPGR (Retinitis Pigmentosa GTPase Regulator) gene that was isolated from the RP3 region is mutated in 20% of North American families with XLRP. From mutation analysis of 27 independent XLRP families, we have identified five novel RPGR mutations in 5 of the families (160delA, 789 A>T, IVS8+1 G>C, 1147insT and 1366 G>A). One of these mutations was detected in a family from Chile.

Molecular genetics is an important tool to elucidate the cause of hereditary diseases. One of the strategies used in this type of studies, is to map the gene responsible of the disease to a specific chromosome region. This has helped in the characterization of some genes, but others remain to be identified. Primau Open Angle Glaucoma (POAG) is a hereditary disease that can lead to blindness if untreated. There are six loci for POAG: GLClA on chromosome region lq24.3-q25.2, GLClB (2cenq13), GLClC (3q21-q24), GLClD (8q23), GLClE (10p14p15) y GLClF (7q35-q36). In a study of several POAG Peruvian families we have characterized one that cosegregates with markers of chromosome 2 corresponding to a new reported family for GLCIB located at 2cen-2q13. One additional individual in the family reveals genetic recombination that refines the position to a smaller region in 2cen-q12 eliminating several...

Detección de mutaciones en el gen MYOC/TIRG en pacientes peruanos con glaucoma primario de ángulo abierto. DETECTION OF MUTATIONS IN MYOC/TIRG GENE IN PERUVIAN PRIMARY OPEN ANGLE GLAUCOMA PATIENTS 

Objetivo: Evaluar, in vitro, el efecto genotóxico del extractos de Abuta grand if olia, "Abura"y Al chomea cascaneifolia, "Hiporuro".Material y método: Se realizaron cultivos de linfocitos obtenidos de sangre periférica, agregando los extractos de Abuta grandifolia, "Abuta" y Alchomea castaneifolia, "Hiporuro" a diferentes concentraci ones. Posteriormente, se realizó la evaluación citológica de aberraciones cromosómicas.Resultados: Se encontró u n núm ero elevado de a berra ciones cromosómicas, tanto para el cultivo con Abuta como para el de Hiporuro. Este efecto se observó a d iferentes concenrracionesde extracto.Conclusiones: Las aberraciones cromosómicas encontradas en el presente trabajo, implicarian un efecto genotóxico de ambas plantas medicinales en el sistema in vitro empleado. Se requiere más estud ios a diferentes niveles de orga nización que complementen los res...

The micronuclei test in lymphocyte culture is a validated procedure to study mutagenicity. It consists in detecting damaged interphasic nuclear material produced by chromosome fragmentation or nuclear division errors in 2000 binucleated cells with well defined cytoplasm. Standard protocol derives from blood chromosome preparation with hypotonic and fixing solutions as well as preparing slides by dropping fixed cells. We modified the protocol to improve the number and quality of micronuclei. First, lymphocytes are separated from red cells before culture. After 72 hours, hypotonic and repeated fixer washing steps are eliminated. Cells are put onto slides by spreading instead of dropping. With these modifications we obtained more (about 8 times per slide) and better defined binucleated cells to help micronuclei detection.

El test de micronúcleos en cultivo de linfocitos es una prueba validada para estudiar mutagenicidad. Consiste en detectar material nuclear interfásico dañado, producto de fragmentación cromosómica o errores de división nuclear en 2000 células binucleadas con citoplasma definido. El protocolo estándar deriva de la preparación citológica de cromosomas de sangre periférica con solución hipotónica, lavados de fijador y goteo de láminas. Nosotros proponemos modificaciones para mejorar el número y la observación de los micronúcleos. Primero se purifica linfocitos de glóbulos rojos antes del cultivo, luego de 72 horas, se elimina la solución hipotónica y los lavados repetidos con fijador, y finalmente se coloca las muestras en láminas por frotis en vez de goteo. Con las modificaciones obtenemos mas células binucleadas bien definidas (un promedio de 8 veces más por lámina...

La Revista Peruana de Biología es una publicación de la Universidad Nacional Mayor de San Marcos

We evaluate the use of SSCP (single strand conformational polymorphism), a relatively easy and inexpensive technique for the detection of point mutations with a sensibility around 80% under ideal conditions. To test the technique, we used samples of volunteers whose DNA had been previously characterized for the presence or absence of 5 mitochondrial RFLPs. Optimization of the tests included variations in TBE (1X and 0,5X) and of glycerol concentration (10%, 5% and no glycerol) in polyacrylamide gels. Four out of five RFLPs were detected under the conditions used and could be applied routinely without using restriction enzymes. In addition, the SSCP technique allowed detection of unknown mutations in a 394 bp nucleotide segment of the hypervariable (HVI) region of mtDNA. Differences corresponding to different haplotypes were detected, helping to distinguish groups within the same subtype....

We evaluate the use of SSCP (single strand conformational polymorphism), a relatively easy and inexpensive technique for the detection of point mutations with a sensibility around 80% under ideal conditions. To test the technique, we used samples of volunteers whose DNA had been previously characterized for the presence or absence of 5 mitochondrial RFLPs. Optimization of the tests included variations in TBE (1X and 0,5X) and of glycerol concentration (10%, 5% and no glycerol) in polyacrylamide gels. Four out of five RFLPs were detected under the conditions used and could be applied routinely without using restriction enzymes. In addition, the SSCP technique allowed detection of unknown mutations in a 394 bp nucleotide segment of the hypervariable (HVI) region of mtDNA. Differences corresponding to different haplotypes were detected, helping to distinguish groups within the same subtype....

The molecular characterization of the mutations causing hereditary diseases are important tools for diagnosis, prognosis and eventually treatment. Huntington's disease is a neurodegenerative disease producing spastic uncontrolled movements and is caused by the expansion of a trinucleotide (CAG)n within the first exon of the gene HD located at 4p16. Hemocromatosis is a liver disease causing cirrosis, diabetes and heart problems, in addition one third of patients dies of hepatocarcinoma. Almost all cases of hemocromatosis are due to mutations in the gene HFE at 6p21, being C282Y and H63D the mutations most frequently detected in Europe and USA. We are establishing the molecular diagnosis of different diseases starting with Huntington disease and hemochromatosis as the begining of a service to the Peruvian comunity.

Los tumores estromales gastrointestinales (GIST) son neoplasias mesenquimales que típicamente surgen a nivel del estómago, intestino delgado, colon, y otros sitios en la cavidad abdominal y su identificación se ha incrementado por mejoras en los criterios de detección. La mayor parte de los tumores GIST son causados por mutaciones activadoras en los genes de receptores transmembranares tirosina quinasa c-KIT y receptor alpha del factor de crecimiento derivado de plaquetas (PDGFRA). Las mutaciones causales de GIST se restringen solo a ciertas regiones del gen que corresponden a importantes zonas funcionales de c-KIT o PDGFRA. Se reporta que hasta 70% de casos de GIST se debe a mutaciones en el exón 11 del gen c-Kit que corresponde a la región yuxtamembrana del receptor. La región y el tipo de mutación determinan diferencialmente cómo se desarrolla la neoplasia, el pronóstico y s...

Genetics and Molecular Biology es una publicación de la Sociedade Brasileira de Genética

La Revista de Gastroenterología del Perú es una publicación de la Sociedad de Gastroenterología del Perú

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La Revista Peruana de Biología es una publicación de la Universidad Nacional Mayor de San Marcos

ldentification of a causative deletion of gastrointestinal stromal tumor (gist) by the analysis of the KlT and PDGFRA genes

Introducción: La warfarina es un anticoagulante cuya eficacia depende de alcanzar y mantener un INR (International Normalised Ratio) en rangos terapéutico. Hasta el 60% de variabilidad dosis-respuesta interindividual puede ser explicada por fármacogenes, al respecto no existen estudios en el Perú. Se estudio el efecto del gen CYP4F2 en la dosis de warfarina en pacientes peruanos. Material y Métodos: Se realizó un estudio observacional descriptivo y ambispectivo, con pacientes atendidos en el Servicio de Hematología del Hospital Grau ESSALUD, Lima Perú, seleccionados por muestreo no probabilístico por conveniencia. Los criterios inclusión fueron pacientes anticoagulados por más de tres meses y con dosis estables de warfarina (misma dosis por al menos tres atenciones en consultorio externo y con un INR en rangos terapéuticos de 2,5-3,5). Se realizó análisis del gen CYP4F2, rs...

OBJETIVOEstandarizar la prueba del Multiplex PCR para identificar las deleciones más frecuentes que incluye nueve exones: 45, 48, 19, 17, 51, 8, 12, 44 y 4 del gen DMD cuyas mutaciones producen las distrofias musculares de Duchenne y de Becker..MATERIAL Y MÉTODOLa prueba fue realizada con 9 individuos, usando DNA obtenido de sangre periférica. De ellos, incluyendo 2 hermanos, tenían diagnóstico clínico de distrofia muscular compatible con DMD. Nueve pares de primers de los exones mencionados se usaron simultáneamente en una amplificación PCR y analizados por geles de agarosa y acrilamida. Uno de los pacientes (DMD-1) tenía diagnóstico molecular de deleción del exón 45 (control positivo) y 5 controles sanos (controles negativos).RESULTADOSLos controles normales mostraron segmentos normales del tamaño esperado de los 9 exones luego de la amplificación PCR. El paciente DMD-1, ...

Introduction: Warfarin is an anticoagulant whose efficacy depends on reaching and maintaining an INR (International Normalized Ratio) within therapeutic ranges. Up to 60% of interindividual dose-response variability can be explained by pharmacogenes, in this regard there are no studies in Peru. We studied the effect of the CYP4F2 gene on the dose of warfarin in Peruvian patients. Material and Methods: A descriptive and ambispective observational study was carried out with patients seen in the Grau ESSALUD Hospital Hematology Service, Lima, Peru, selected by non-probabilistic convenience sampling. The inclusion criteria were patients anticoagulated for more than three months and with stable doses of warfarin (same dose for at least three outpatient visits and with an INR in therapeutic ranges of 2.5-3.5). Analysis of the CYP4F2 gene was performed by taking a DNA sample from peripheral blo...

Existe un artículo similar de los mismos autores escrito en español en la revista Horizonte Médico, vol.14, no.4 (2014).