Influence of ethnicity on the distribution of genetic polymorphisms associated with risk of chronic liver disease in South American populations

BACKGROUND: The global burden of chronic liver disease is rising. Besides environmental, behavioral, viral and metabolic factors, genetic polymorphisms in patatin-like phospholipase-3 (PNPLA3) and vitamin D receptor (VDR) genes have been related to the development of chronic liver disease and progression towards liver cancer. Although their prevalence differs remarkably among ethnic groups, the frequency of these polymorphisms in South American populations -whose genetic background is highly admixed- has been poorly studied. Hence, the aim of this study was to characterize polymorphisms related to chronic liver disease and their association with the genetic ancestry of South American populations. RESULTS: DNA samples from 258 healthy unrelated male volunteers were analyzed. The frequencies of G and C alleles of rs738409 polymorphism (PNPLA3 gene) were 74 % and 26 %, respectively; whereas the bAt (CCA) haplotype (VDR gene) was observed in 32.5 % of the samples. The GG genotype of PNPLA3 rs738409 and the bAt (CCA) haplotype -associated with an increased risk of chronic liver disease and progression towards liver cancer- were significantly more frequent among samples exhibiting maternal and paternal Native American haplogroups (63.7 % and 64.6 %), intermediate among admixed samples (45.1 % and 44.9 %; p = 0.03) and the lowest for Non-native American ancestry (30.1 % and 29.6 %; p = 0.001 and p = 0.0008). CONCLUSIONS: These results suggest that individuals with Native American ancestry might have a high risk of chronic liver disorders and cancer. Furthermore, these data not only support the molecular evaluation of ancestry in multi-ethnic population studies, but also suggest that the characterization of these variants in South American populations may be useful for establishing public health policies aimed at high risk ethnic communities.Fil: Pontoriero, Ana Cecilia. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Trinks, Julieta. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hulaniuk, María Laura. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; ArgentinaFil: Caputo, Mariela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fortuny, Lisandro. Hospital Italiano; ArgentinaFil: Burgos Pratx, Leandro. Hospital Italiano; ArgentinaFil: Frías, Analía. Hospital Materno Infantil “Ramón Sardá”; ArgentinaFil: Torres, Oscar. Hospital Materno Infantil “Ramón Sardá”; ArgentinaFil: Nuñez, Félix. Hospital Italiano; ArgentinaFil: Gadano, Adrián. Hospital Italiano; ArgentinaFil: Argibay, Pab lo. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Corach, Daniel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Flichman, Diego Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Virología; Argentin

Distribution of genetic polymorphisms associated to hepatitis c virus (HCV) antiviral response in a multiethnic and admixed population

2 p.Single-nucleotide polymorphisms (SNPs) near IL28B and ITPA genes have been described as predictors of response to antiviral treatment and ribavirin induced-hemolytic anemia in HCV patients, respectively. The prevalence of these polymorphisms differs among ethnic groups; however, there is a paucity of information about South American populations. Hence, the aim of this study was to determine the prevalence of these SNPs in the healthy population of different ethnic groups residing in Argentina.http://www.viral-hep.org/default.aspxFil: Thinks, Julieta. Hospital Italiano de Buenos Aires. Instituto de Ciencias Básicas y Medicina Experimental; Argentina.Fil: Caputo, Mariela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina.Fil: Hulaniuk, María Laura. Hospital Italiano de Buenos Aires. Instituto de Ciencias Básicas y Medicina Experimental; Argentina.Fil: Burgos Pratx, Leandro. Servicio de Medicina Transfusional; Argentina.Fil: Ré, Viviana. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología Dr. José María Vanella; Argentina.Fil: Fortuny, Lisandro. Servicio de Medicina Transfusional; Argentina.Fil: Frías, Analía. Servicio de Medicina Transfusional; Argentina.Fil: Torres, Oscar. Servicio de Medicina Transfusional; Argentina.Fil: Nuñez, Félix. Servicio de Medicina Transfusional; Argentina.Fil: Gadano, Adrián. Servicio de Hepatología; Argentina.Fil: Corach, Daniel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina.Fil: Flichman, Diego Martín. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina.Otras Ciencias de la Salu

The seasonal distribution of immune thrombotic thrombocytopenic purpura is influenced by geography: Epidemiologic findings from a multi‐center analysis of 719 disease episodes

Abstract Prior studies have suggested that immune thrombotic thrombocytopenic purpura (iTTP) may display seasonal variation; however, methodologic limitations and sample sizes have diminished the ability to perform a rigorous assessment. This 5‐year retrospective study assessed the epidemiology of iTTP and determined whether it displays a seasonal pattern. Patients with both initial and relapsed iTTP (defined as a disintegrin and metalloprotease with thrombospondin type motifs 13 activity <10%) from 24 tertiary centers in Australia, Canada, France, Greece, Italy, Spain, and the US were included. Seasons were defined as: Northern Hemisphere—winter (December–February); spring (March–May); summer (June–August); autumn (September–November) and Southern Hemisphere—winter (June–August); spring (September–November); summer (December–February); autumn (March–May). Additional outcomes included the mean temperature in months with and without an iTTP episode at each site. A total of 583 patients experienced 719 iTTP episodes. The observed proportion of iTTP episodes during the winter was significantly greater than expected if equally distributed across seasons (28.5%, 205/719, 25.3%–31.9%; p = .03). Distance from the equator and mean temperature deviation both positively correlated with the proportion of iTTP episodes during winter. Acute iTTP episodes were associated with the winter season and colder temperatures, with a second peak during summer. Occurrence during winter was most pronounced at sites further from the equator and/or with greater annual temperature deviations. Understanding the etiologies underlying seasonal patterns of disease may assist in discovery and development of future preventative therapies and inform models for resource utilization