[Study of the association between the polymorphism of the TNF-α gene and prostate cáncer]. / Estudio de la asociación entre el polimorfismo del gen TNFα y el cáncer de próstata.

BACKGROUND: Prostate cancer is the third cause of cancer death in men in the Western hemisphere and the second cause of cancer death in Zulian men from Venezuela. OBJECTIVE: To determine whether polymorphisms 308 and 238 of the tumor necrosis factor alpha (TNF-α) gene are associated with prostate cancer. METHODS: The DNA that was extracted from the peripheral blood of 40 patients with prostatic specific antigen and 40 controls was amplified by PCR plus digestion with enzymes NcoI and MspI. RESULTS: In the patients, genotypes of the TNF-α-238 polymorphism were observed in 90% GG and 10% GA; in controls, in 97.5% GG and 2.5% GA, odds ratio (OR) = 4,000 for GA. In the patients, genotypes of TNF-α-308 polymorphism were identified in 85% GG and 15% GA, and in controls in 72.5% GG and 27.5% GA, OR = 0.545 for GA and 1.172 for GG. The allelic frequencies for TNF-α-238 in patients were 95% for G and 5% for A; in controls, 98.75% for G and 1.25% for A, with OR = 4,000 for A. The allelic frequencies for TNF-α-308 in the patients were 92.5% for G and 7.5% for A. CONCLUSIONS: There weren't any statistically significant associations. The allele A of the TNF-α-238 polymorphism resulted in a considerable risk factor for prostate cancer.

Antecedentes: El cáncer de próstata es la tercera causa de muerte por cáncer en hombres del hemisferio occidental y la segunda en zulianos de Venezuela. Objetivo: Determinar si los polimorfismos 308 y 238 del gen TNFα están asociados con cáncer de próstata. Métodos: El ADN extraído de sangre periférica de 40 pacientes con antígeno prostático específico y 40 controles fue amplificado por reacción en cadena de la polimerasa más digestión con enzimas NcoI y MspI. Resultados: Respecto al polimorfismo 238 del gen TNFα, en los pacientes se observó 90 % de genotipo GG y 10 % de GA; en los controles, 97.5 % de GG y 2.5 % de GA, razón de momios (RM) = 4.000 para GA. En cuanto al polimorfismo 308, en los pacientes se identificó 85 % de genotipo GG y 15 % de GA; y en los controles, 72.5 % de GG y 27.5 % de GA, RM = 0.545 para GA y 1.172 para GG. Las frecuencias alélicas de TNFα-238 en los pacientes fue de 95 % de G y 5 % de A; en los controles, 98.75 % de G y 1.25 % de A, con RM = 4.000 para A. Las frecuencias alélicas para TNFα-308 en los pacientes fueron 92.5 % de G y 7.5 % de A. Conclusiones: No existieron asociaciones estadísticamente significativas. El alelo A del polimorfismo 238 del gen TNF-α resultó de riesgo para cáncer de próstata.

Historical and ecological drivers of the spatial pattern of Chondrichthyes species richness in the Mediterranean Sea.

Chondrichthyes, which include Elasmobranchii (sharks and batoids) and Holocephali (chimaeras), are a relatively small group in the Mediterranean Sea (89 species) playing a key role in the ecosystems where they are found. At present, many species of this group are threatened as a result of anthropogenic effects, including fishing activity. Knowledge of the spatial distribution of these species is of great importance to understand their ecological role and for the efficient management of their populations, particularly if affected by fisheries. This study aims to analyze the spatial patterns of the distribution of Chondrichthyes species richness in the Mediterranean Sea. Information provided by the studied countries was used to model geographical and ecological variables affecting the Chondrichthyes species richness. The species were distributed in 16 Operational Geographical Units (OGUs), derived from the Geographical Sub-Areas (GSA) adopted by the General Fisheries Commission of the Mediterranean Sea (GFCM). Regression analyses with the species richness as a target variable were adjusted with a set of environmental and geographical variables, being the model that links richness of Chondrichthyes species with distance to the Strait of Gibraltar and number of taxonomic families of bony fishes the one that best explains it. This suggests that both historical and ecological factors affect the current distribution of Chondrichthyes within the Mediterranean Sea.

Effect of the parental origin of the X-chromosome on the clinical features, associated complications, the two-year-response to growth hormone (rhGH) and the biochemical profile in patients with turner syndrome.

BACKGROUND: It is possible that genes on the X chromosome are expressed differently depending of its parental origin. The objective of this study was to determine the influence of the parental origin of the X-chromosome on phenotypic variability, response to rhGH and on the biochemical profile of TS patients. METHODS: This was a cross-sectional multicenter correlational study carried out over three years in six Latin-American university hospitals. Unrelated 45,X TS patients (n = 93; 18.3 ± 8.5 years )) were evaluated. A subgroup (n = 34) of the patients were prospectively treated with rhGH over two years. DNA profiles of patients and their mothers were compared to determine the parental origin of the retained X-chromosome through 10 polymorphic X-chromosome-STRs. The association with clinical features, biochemical profiles and anthropometric data at the beginning and after two years of rhGH treatment was determined. RESULTS: Seventy two percent of patients retained the maternal X chromosome (Xm). A trend towards significance between maternal height and patients final height (p ≤ 0.07) in 45,Xm subjects was observed. There was no correlation between paternal height and patient height. No differences were detected between both groups in regard to dysmorphic features, classical malformations or increase in the height-SDS after rhGH. There were higher levels of triglycerides, total and LDL cholesterol in patients >20 years who retained the Xm. CONCLUSIONS: The parental origin of the retained X chromosome may influence lipid metabolism in TS patients, but its effect on growth seems to be minimal. No parental-origin-effect on the phenotypic features, associated anomalies and on the growth response to rhGH was found in 45,X TS individuals.

[G138A polymorphism of the RNASEL gene and its association with the development of prostate cancer. Preliminary study]. / Polimorfismo G1385A del gen RNASEL y su asociación con el desarrollo de cáncer de próstata. Estudio preliminar.

Prostate Cancer (CAP), is a complex disease with a multifactorial origin. It is characterized by heterogenous patterns of growth of neoplasic tissue, varying widely in its progression, age of beginning and therapy response. It is considered as the second most common cause of death by cancer in men and, it has been estimated, that one of five, suffers of CAP through the course of his life. The genetic etiology of neoplasic transformation of normal prostate cells is still not known; nevertheless, investigations in epidemiology have demonstrated a strong genetic component in its development, suggesting so much a pattern of mendelian inheritance as the presence of loci of susceptibility throughout the human genome. It has been described a cromosomic location related to the CAP in locus 1q24-25, denominated HPC1, where the gene RNASEL is located, and the seggregation of its alleles has been associated with the development of CAP in numerous familiar groups. The RNASEL gene codifies for a ribonuclease protein that degrades vi-ral and cellular ARN and takes part in the apoptosis. A decrease of the enzymatic activity up to three times in carriers of the G1385A polymorphism of this gene has been reported, and the same has been associated frequently with the development of CAP. Using a variant of the Polymerase Chain Reaction, Allele specific amplification, this investigation had as objective to determine the association between variant G1385A and CAP, in a sample of 103 masculine individuals with and without CAP, pertaining to the population of Maracaibo, Venezuela. An association between these variants and CAP could not be demonstrated.

[C677T polymorphism of the methylentetrahydrofolate reductase gene as risk factor in women with recurrent abortion]. / Polimorfismo C677T del gen de la Metiltetrahidrofolato Reductasa como factor de riesgo en mujeres con aborto recurrente.

The pathogenesis of recurrent spontaneous abortion is multifactorial, presumably involving the interaction of several genetic and environmental factors. The methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism has been implicated as risk factor for recurrent spontaneous abortion (RA). The main objective of this research was to investigate the association between the C677T polymorphism of the MTHFR gene as a genetic risk factor for idiopathic RA. Molecular analysis was performed in 80 DNA samples from 30 patients with RA and among 50 healthy control subjects. Using the Polymerase Chain Reaction (PCR), a 198 bp (bases pairs) fragment, was digested with the restriction enzyme Hinf1, which can recognize the C > T substitution responsible for the polymorphism. 677T MTHFR allele frequencies for group with RA and the control group were 35% and 33%, respectively and 677C MTHFR allele frequencies were 65% and 67%, respectively. There was no significant difference in allele frequency between these two groups. The data presented in this study fail to support the relationship between MTHFR C677T polymorphism and risk in women with RA.

Polimorfismo C677T del gen de la metiltetrahidrofolato reductasa como factor de riesgo en mujeres con aborto recurrente / C677T polymorphism of the methylentetrahydrofolate reductase gene as risk factor in women with recurrent abortion

La patogénesis de los abortos espontáneos recurrentes es multifactorial; probablemente se debe a la interacción de varios factores ambientales y genéticos. El polimorfismo C677T del gen de la metiltetrahidrofolato reductasa (MTHFR), ha sido implicado como factor de riesgo para aborto espontáneo recurrente (AR). El objetivo de este trabajo fue investigar la asociación del polimorfismo C677T de la MTHFR como factor de riesgo en AR idiopático. Se analizaron 80 muestras de ADN, correspondientes a 30 mujeres con AR y a 50 mujeres controles. A través de la reacción en cadena de la polimerasa (PCR) se amplificó un fragmento de 198 pares de base (pb), el cual se sometió a digestión con la enzima de restricción HinfI, que reconoce el sitio de restricción creado por la transición C>T en la posición 677. La frecuencia alélica de la MTHFR en el grupo de estudio y control fue 35% y 33% respectivamente; para el alelo T y 65% y 67% respectivamente, para el alelo C. No se encontró diferencia significativa entre el alelo T ni el C al ser comparados en ambos grupos. No se demostró un factor predisponente entre el polimorfismo C677T de la MTHFR y el AR en la muestra estudiada.

The pathogenesis of recurrent spontaneous abortion is multifactorial, presumably involving the interaction of several genetic and environmental factors. The methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism has been implicated as risk factor for recurrent spontaneous abortion (RA). The main objective of this research was to investigate the association between the C677T polymorphism of the MTHFR gene as a genetic risk factor for idiopathic RA. Molecular analysis was performed in 80 DNA samples from 30 patients with RA and among 50 healthy control subjects. Using the Polymerase Chain Reaction (PCR), a 198 bp (bases pairs) fragment, was digested with the restriction enzyme HinfI, which can recognize the C > T substitution responsible for the polymorphism. 677T MTHFR allele frequencies for group with RA and the control group were 35% and 33%, respectively and 677C MTHFR allele frequencies were 65% and 67%, respectively. There was no significant difference in allele frequency between these two groups. The data presented in this study fail to support the relationship between MTHFR C677T polymorphism and risk in women with RA.

Polimorfismo G1385A del gen RNASEL y su asociación con el desarrollo de cáncer de próstota: estudio preliminar / G138A polymorphism of the RANASEL gene and its association with the development of prostate cancer: preliminary study

El cáncer de Próstata (CAP), es una enfermedad compleja de origen multifactorial. Se caracteriza por patrones heterogéneos de crecimiento de tejido neoplásico, que varían ampliamente en su progresión, edad de aparición y respuesta al tratamiento. Se considera la segunda causa más común de muerte por malignidad en hombres y se estima que uno de cada cinco padece de CAP en el curso de su vida. La etiología genética de la transformación neoplásica de las células prostáticas normales aún es desconocida, sin embargo, investigaciones epidemiológicas han demostrado un fuerte componente genético en su desarrollo, y sugieren tanto un patrón de herencia mendeliana como la presencia de loci de susceptibilidad a lo largo del genoma humano. Se ha descrito una región cromosómica relacionada con el CAP denominada como HPC1, en el locus 1q24-25, donde se ubica el gen RNASEL, y las mutaciones en el mismo, se han asociado con la presencia del CAP en múltiples grupos familiares. EL gen RNASEL codifica para una ribonucleasa que degrada ARN viral y celular y que interviene en la apoptosis. Se ha reportado disminución de la actividad enzimática de hasta tres veces en portadores del polimorfismo G1385A de este gen, y la misma se ha asociado frecuentemente con el desarrollo del CAP. Mediante la utilización de una variante de la Reacción en Cadena de la Polimerasa (RCP), una amplificación alelo específica, se estudiaron 103 individuos masculinos con y sin CAP pertenecientes a la población de Maracaibo, Venezuela, evidenciándose ausencia de asociación.

Prostate Cancer (CAP), is a complex disease with a multifactorial origin. It is characterized by heterogenous patterns of growth of neoplasic tissue, varying widely in its progression, age of beginning and therapy response. It is considered as the second most common cause of death by cancer in men and, it has been estimated, that one of five, suffers of CAP through the course of his life. The genetic etiology of neoplasic transformation of normal prostate cells is still not known; nevertheless, investigations in epidemiology have demonstrated a strong genetic component in its development, suggesting so much a pattern of mendelian inheritance as the presence of loci of susceptibility throughout the human genome. It has been described a cromosomic location related to the CAP in locus 1q24-25, denominated HPC1, where the gene RNASEL is located, and the seggregation of its alleles has been associated with the development of CAP in numerous familiar groups. The RNASEL gene codifies for a ribonuclease protein that degrades viral and cellular ARN and takes part in the apoptosis. A decrease of the enzymatic activity up to three times in carriers of the G1385A polymorphism of this gene has been reported, and the same has been associated frequently with the development of CAP. Using a variant of the Polymerase Chain Reaction, Allele specific amplification, this investigation had as objective to determine the association between variant G1385A and CAP, in a sample of 103 masculine individuals with and without CAP, pertaining to the population of Maracaibo, Venezuela, An association between these variants and CAP could not be demonstrated.