RESUMOA predisposição genética ao diabetes melito tipo 1 (DM1) é associada a múltiplos genes do sistema de histocompatibilidade humano (HLA) de classe II. Em caucasianos, os antígenos HLA-DR3 e -DR4 são associados à susceptibilidade e o -DR2, à proteção. No Brasil, um país constituído por grande miscigenação entre caucasianos europeus, índios nativos e negros africanos, a base genética do DM1 tem sido pouco estudada. O objetivo desse trabalho foi apresentar uma revisão crítica dos artigos indexados nos bancos de dados MEDLINE e LILACS-BIREME sobre a associação do HLA com DM1 em brasileiros. Todos os oito estudos encontrados foram realizados no sudeste do país. A susceptibilidade imunogenética para o DM1 em brasileiros foi associada com os alelos HLA-DRB1*03, -DRB1*04, -DQB1*0201, -DQB1*0302 e a proteção com os alelos -DQB1*0602 e -DQB1*0301 e os antígenos -DR2 e -DR7. Por ser o Brasil constituído por grande miscigenação, não se pode extrapolar para todo o país estudos realizados em apenas uma região. Faz-se necessário pesquisar populações de várias regiões, analisando sua diversidade alélica para identificar novas associações ou reforçar aquelas já existentes. Esse conhecimento contribuirá para futuras intervenções profiláticas e terapêuticas nos grupos de brasileiros com maior risco de desenvolver DM1. The genetic predisposition to type 1 diabetes (DM1) is associated with genes of the human leukocyte antigen (HLA) system, specially the HLA-DR and -DQ. In Caucasians, the HLA-DR3 and -DR4 antigens are associated with susceptibility and the -DR2, with protection. In Brazil, a country with a large miscegenation of Europeans Caucasians, Native Amerindians and African Blacks, the genetic basis of DM1 has not been adequately studied. The aim of this paper is to present a critical review of articles indexed in the MEDLINE and LILACS-BIREME data basis about the association of HLA with DM1 in Brazilians. Eight papers, all of them from the Southeast region, were found. Immunogenetic susceptibility to DM1 in Brazilians was associated with HLA-DRB1*03, -DRB*04, -DQB1*0201, -DQB1*0302 alleles, and protection against DM1 was associated with HLA-DQB1*0602, -DQB1*0301 alleles and -DR2 and -DR7 antigens. Since the Brazilian population is not racially homogeneous, it is not possible to extrapolate studies from a single region to the remaining of the country. It is necessary to study populations from different regions to identify new associations or to strengthen associations with the ones already identified. This knowledge will con-

Abstract:The participation of the human histocompatibility system (HLA: human leukocyte antigens) in the pathogenesis of autoimmune diseases is well known. Situated on the short arm of chromosome 6, the HLA system is very polymorphic and has the capacity to confer susceptibility or resistance to different diseases. In Dermatology, this system has an important participation in the pathogenesis and natural course of various diseases. The strength and type of association differ with conditions and sometimes with the ethnic-racial group studied. The discovery of molecular methods to typify HLA alleles and recent updates in its nomenclature has contributed to a better understanding of this system. Unfortunately, this information has not been adequately transmitted in the literature, hindering identification of the association of the HLA with skin diseases. In this review, some aspects of the HLA system are discussed, such as methods of detection, nomenclature and association with vitiligo, pemphigus, psoriasis, lupus erythematosus, scabies, cutaneous leishmaniasis, leprosy, paracoccidiodomycosis and atopic dermatitis.