Made available in DSpace on 2014-12-17T14:16:20Z (GMT). No. of bitstreams: 1 GiocondaDRL.pdf: 1031402 bytes, checksum: 0016e69e527bddffea93909fa2748a03 (MD5) Previous issue date: 2007-08-29 / Hereditary Hemochromatosis (HH) is a genetic disease caused by high iron absorption and deposition in several organs. This accumulation results in clinical disturbances such as cirrhosis, arthritis, cardiopathies, diabetes, sexual disorders and skin darkening. The H63D and C282Y mutations are well defined in the hemochromatosis etiology. The aim of this paper was that of identifying the H63D and C282Y genetical mutations in the hemochromatosis gene and the frequency assessment of these mutations in the HFE protein gene in patients with hyperferritin which are sent to the DNA Center laboratory in Natal, state of Rio Grande do Norte. This paper also evaluates the HH H63D and C282Y gene mutations genotype correlation with the serum ferritin concentration, glucose, alanine aminotransferasis, aspartato aminotransferasis, gama glutamil transferasis and with the clinical complications and also the interrelation with life habits including alcoholism and iron overload. The biochemical dosages and molecule analyses are done respectively by the enzymatic method and PCR with enzymatic restriction. Out of the 183 patients investigated, 51,4% showed no mutation and 48,6% showed some type of mutation: 5,0% were C282Y heterozygous mutation; 1,1%, C282Y homozygous mutation; 31%, H63D heterozygous mutation; 8,7%, H63D homozygous mutation; and 3,3%, heterozygous for the mutation in both genes. As to gender, we observed a greater percentage of cases with molecular alteration in men in relation to women in the two evaluated mutations. The individuals with negative results showed clinical and lab signs which indicate hemochromatosis that other genes could be involved in the iron metabolism. Due to the high prevalence of hemochromatosis and taking into account that hemochromatosis is considered a public health matter, its gravity being preventable and the loss treatment toxicity, the early genetic diagnosis is indicated, especially in patients with high ferritin, and this way it avoids serious clinical manifestations and increases patients' life expectation. Our findings show the importance of doing such genetic studies in individuals suspected of hereditary hemochromatosis due to the high incidence of such a hereditary disease in our region / A hemocromatose heredit?ria (HH) ? uma doen?a gen?tica causada pela absor??o e deposi??o elevada de ferro em v?rios ?rg?os. Este ac?mulo resulta em complica??es cl?nicas como cirrose, artrite, cardiopatias, diabetes, desordens sexuais e escurecimento da pele. As muta??es H63D e C282Y est?o bem definidas na etiologia da hemocromatose. O objetivo deste trabalho foi a identifica??o das muta??es gen?ticas H63D e C282Y no gene da Hemocromatose e avalia??o da freq??ncia dessas muta??es no gene da prote?na HFE em pacientes com hiperferritinemia que s?o encaminhados ao laborat?rio DNA Center Natal / RN. Al?m disso, avaliar a correla??o dos gen?tipos das muta??es H63D e C282Y do gene da HH com a concentra??o s?rica da ferritina, glicose, alanina aminotransferase, aspartato minotransferase, gt e com as complica??es cl?nicas e ainda a interrela??o com os h?bitos de vida incluindo o etilismo e dieta com sobrecarga de ferro. As dosagens bioqu?micas e an?lises moleculares foram realizadas respectivamente atrav?s do m?todo enzim?tico e PCR com restri??o enzim?tica. Dos 183 pacientes investigados 51,4% apresentaram aus?ncia de muta??o e 48,6% com algum tipo de muta??o: 5,0% C282Y heterozigoto mutado; 1,1% C282Y homozigoto mutado; 31% H63D heterozigoto mutado; 8,7% H63D homozigoto mutado; e 3,3% heterozigoto para a muta??o em ambos os genes. Com rela??o ao sexo, observou-se o maior percentual de casos com altera??o molecular em homens em rela??o a mulheres nas duas muta??es avaliadas. Os indiv?duos com resultados negativos apresentaram sinais cl?nicos e laboratoriais indicativos de hemocromatose sugerindo que outros genes poder?o estar envolvidos no metabolismo do ferro. Devido ? alta preval?ncia da hemocromatose, e tendo em vista que a hemocromatose ? considerada um problema de sa?de p?blica, sua gravidade ser preven?vel e a baixa toxicidade do tratamento, o diagn?stico gen?tico precoce torna-se indicado, principalmente nos pacientes com ferritina elevada, e com isso evitar manifesta??es cl?nicas graves e aumentar a expectativa de vida dos pacientes com esta doen?a. Nossos achados mostram a import?ncia da realiza??o de estudos gen?ticos em indiv?duos com suspeita de hemocromatose heredit?ria em virtude de elevada incid?ncia dessa doen?a de cunho heredit?rio em nossa regi?o

La Hemocromatosis Hereditaria (HH) es una enfermedad genética, autosómica recesiva, caracterizada por una absorción masiva de hierro procedente de la dieta. Con el tiempo el exceso de hierro se acumula en diferentes órganos como en hígado, páncreas, corazón, glándulas endocrinas y articulaciones produciendo la alteración de los mismos. La clínica característica de la Hemocromatosis Hereditaria se presenta con cirrosis hepática, que puede desembocar en un carcinoma hepatocelular, diabetes, arritmias, pigmentación oscura de la piel, atralgias, hipogonadismo e hipotiroidismo. La enfermedad se detecta mediante análisis bioquímicos de ferritina sérica y saturación de transferrina, una biopsia hepática y/o un estudio genético de las mutaciones del gen HFE, principalmente las mutaciones C282Y y H63D. La Hemocromatosis Hereditaria es una enfermedad que presenta un tratamiento sencillo y barato, que consiste en extracciones periódicas de sangre o flebotomías para reducir de esta manera el exceso de hierro que se ha acumulado dentro del organismo. Si el tratamiento se realiza antes de que se produzcan daños en los órganos internos se previene las complicaciones clínicas de la enfermedad y se reestablece la esperanza de vida del paciente, por lo que un diagnóstico precoz es esencial para llevar a cabo un tratamiento con éxito en esta enfermedad.En esta tesis se centra en la Hemocromatosis Hereditaria a nivel clínico y básico, y en ella se han abordado los siguientes puntos:- Detección de la frecuencia de las mutaciones C282Y y H63D del gen HFE en 107 pacientes con Hemocromatosis Hereditaria y en controles de la población española.- Se describe que el genotipo C282Y/H63D es más frecuente en pacientes con Hemocromatosis Hereditaria que en controles y que la mayoría de los pacientes con Hemocromatosis Hereditaria (91,6%) presentan los genotipos C282Y/C282Y o C282Y/H63D del gen HFE.- Cribado de 5370 donantes de sangre para las mutaciones C282Y y H63D del gen HFE, en el que se detectan 8 individuos C282Y/C282Y y 74 individuos C282Y/H63D. Se describe la penetrancia de los genotipos C282Y/C282Y y C282Y/H63D.- Detección de parámetros bioquímicos de saturación de transferrina, hierro sérico y ferritina sérica en grupos de individuos con genotipos concretos, detectándose diferencias significativas entre el genotipado C282Y/C282Y y los otros genotipos. - Búsqueda de nuevas mutaciones en 9 pacientes con Hemocromatosis Hereditaria sin los genotipos C282Y/C282Y ni C282Y/H63D en los genes HFE, TFR2 y FPN1. Se describe la existencia de diversos polimorfismos.- Secuenciación de la región promotora del gen HFE en 25 pacientes Italianos de Hemocromatosis Hereditaria sin las mutaciones C282Y ni H63D. Se detecta el cambio -48 C/G en el 5'UTR del gen HFE en un paciente italiano de Hemocromatosis Hereditaria sin las mutaciones C282Y ni H63D.- Estudio comparativo de la zona promotora del gen HFE en humanos, rata y ratón, detectándose elementos reguladores conservados mediante técnicas de comparación computacionales. Identificación de 1398 pb correspondientes a la región promotora del gen HFE de rata y detección de regiones reguladoras del promotor de rata mediante experimentos de retardación en gel. Se estudia el promotor humano del gen HFE mediante experimentos de "Reporter gene" con luciferasa.- Detección de 5 formas de "splicing" en el gen HFE humano mediante experimentos de RT-PCR en la línea celular HepG2.- Se alarga la región 3' UTR del gen HFE humano (exón 7) en 1512 pares de bases y la región 3' UTR del gen HFE de ratón (exón 6) en 1990 pares de bases mediante experimentos de RT-PCR, 3' RACE y "Northern Blot".- Detección de 2 nuevas formas de terminación del gen HFE humano en el exón 6 mediante experimentos de 3' RACE.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-04T19:56:38Z No. of bitstreams: 1 GiocondaDiasRodriguesLeao_TESE.pdf: 44025376 bytes, checksum: 9da025324f9108141027f1f3a1cc3e16 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-05T20:29:30Z (GMT) No. of bitstreams: 1 GiocondaDiasRodriguesLeao_TESE.pdf: 44025376 bytes, checksum: 9da025324f9108141027f1f3a1cc3e16 (MD5) / Made available in DSpace on 2016-01-05T20:29:30Z (GMT). No. of bitstreams: 1 GiocondaDiasRodriguesLeao_TESE.pdf: 44025376 bytes, checksum: 9da025324f9108141027f1f3a1cc3e16 (MD5) Previous issue date: 2013-05-17 / Background & Aims: HFE-associated Hereditary Hemochromatosis (HH) is one of the most frequent autosomal recessive disease in the caucasian population, caused by the high absorption and deposition of iron in several organs. This accumulation results in several clinical complications such as cirrhosis, arthritis, cardiopathies, diabetes, sexual disorders and skin darkening. Although most of the cases are homozygous individuals for the C282Y mutation, another two mutations, H63D and S65C, have been reported to be associated with milder forms of the disease. The objective is to avaluate the distribution of C282Y, H63D and S65C mutations in the HFE gene in patients with suspected HH in the state of Rio Grande do Norte, Brazil. Methods: Samples of peripheral blood were taken from 335 patients originating from Natal-RN, a city in northeastern Brazil with suspected of HH and which were screened for the HFE gene C282Y, H63D and S65C mutations, using molecular genetics assays (Polymerase Chain Reaction- Restriction Fragments Length Polymorphism). The main criterion for including such patients in the study was the increasing of persistent serum ferritin in individuals aged between 18 and 70 or older, both males and females. As to the exclusion criteria, individuals holding hemolytical anemia, talassemy and previously report of blood transfusion did not take part of the study. Results: Out of the 335 patients studied, 143 patients showed absence of mutation and 195 showed some kind of mutation in the HFE gene: 07/335 (2,08%) were homozigous C282Y, 25/335 heterozygous C282Y, 25/335 (7,46%) were homozigous H63D, 115/335 (34,32%) heterozygous H63D, 5/335 (1,48%) heterozygous S65D, 11/ 335 (3,28%) and were double heterozygous (H63D/C282Y). None patients were Homozygous S65D and S65D heterozygous (S65D/H63D and S65D/C282Y). Conclusions. The distribution of the HFE gene C282Y, H63D and S65C mutations found in our group matches the tendencies observed in other European countries. Due to the high prevalence of hemochromatosis, its seriousness and easy treatment, the genetic diagnosis of HH has become a dream, especially in the high risk group.