Analysis of Gene Recombination between HLA-B and -DRB1, HLA-DQB1 and -DPB1 Loci / 中国实验血液学杂志

OBJECTIVE@#To investigate the recombinations within the human leukocyte antigen (HLA) region in two families.@*METHODS@#Genomic DNA was extracted from the peripheral blood specimens of the different family members. HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci were genotyped using polymerase chain reaction-sequence specific oligonucleotide probing technique (PCR-SSO) and next-generation sequencing technique. HLA haplotype was determined by genetic analysis of the pedigree.@*RESULTS@#The haplotypes of HLA-A*11:01~C*03:04~B*13:01~DRB1*12:02~DQB1*03:01~DPB1*05:01:01G and HLA-A*03:01~C*04:01~B*35:03~DRB1*12:01~DQB1*03:01~DPB1*04:01:01G in the family 1 were recombined between HLA-B and HLA-DRB1 loci, which formed the haplotype of HLA-A*11:01~C*03:04~B*13:01~DRB1* 12:01~DQB1*03:01~DPB1*04:01:01G. The haplotypes of HLA-A *02:06~C*03:03~B*35:01~DRB1*08:02~DQB1*04:02~ DPB1*13:01:01G and HLA-A *11:01~C*07:02~B*38:02~DRB1*15:02~DQB1*05:01~DPB1*05:01:01G in the family 2 were recombined between HLA-DQB1 and HLA-DPB1 loci, which formed the haplotype of HLA-A*02:06~C*03:03~B*35:01~ DRB1*08:02~DQB1*04:02~DPB1*05:01:01G.@*CONCLUSION@#The gene recombination events between HLA-B and -DRB1, HLA-DQB1 and -DPB1 loci were found respectively in two Chinese Han families.

HLA-DQA1*04: 01 is related to a higher multiple sclerosis lesion load on T2/Flair MRI sequences / O HLA-DQA1*04: 01 está relacionado com uma alta carga lesional na ressonância magnética em T2/Flair nos pacientes com esclerose múltipla

ABSTRACT Background: The genetic predisposition to multiple sclerosis (MS) is associated with HLA alleles, especially HLA-DRB1*15:01. Objective: To identify associations between findings in magnetic resonance imaging (MRI) and genetic features in a Brazilian cohort of patients with MS. Methods: We retrospectively studied data from 95 consecutive patients with MS. Two independent observers who were blinded to the clinical data identified black holes and enhanced lesions on T1 MRI sequences, and counted and measured contrast-enhanced lesions on T2 and Flair (fluid attenuation inversion recovery) sequences. Cases were classified according to lesion size, number, and volume. The HLA-DRB1, HLA-DQB1, and HLA-DQA1 alleles, and the rs4774, rs3087456, rs6897932, rs731236, and rs1033182 single nucleotide polymorphisms were identified by polymerase chain reaction amplification with sequence-specific primers using the One Lambda Inc. Kit, Canoga Park, CA, USA. Results: Patients with the HLA-DQA1*04:01 allele had lesion load (adjusted for age, sex, and MS duration) above median compared with patients with other HLA-DQA1 alleles (p=0.02). There were no differences among all the other HLA alleles and single nucleotide polymorphisms and lesion load. Conclusions: The correlation of the HLA-DQA1*04:01 allele with a higher lesion load on T2/Flair MRI sequences suggests that the presence of this allele is associated with the risk of greater MS severity.

RESUMO Antecedentes: A predisposição genética para a esclerose múltipla (EM) está associada a alelos HLA, principalmente o HLA-DRB1*15:01. Objetivo: Identificar associações entre lesões na ressonância magnética e características genéticas em uma coorte brasileira de pacientes com EM. Métodos: Estudamos retrospectivamente os dados de 95 pacientes consecutivos com EM. Dois observadores independentes que desconheciam os dados clínicos identificaram "black holes" e lesões realçadas pelo contraste nas sequências de ressonância magnética T1 e contaram e mediram as lesões nas sequências T2 e FLAIR (fluid attenuated inversion recovery). Os casos foram classificados de acordo com tamanho, número e volume da lesão. Os alelos HLA-DRB1, HLA-DQB1 e HLA-DQA1 e os polimorfismos de nucleotídeo único rs4774, rs3087456, rs6897932, rs731236 e rs1033182 foram identificados por amplificação de reação em cadeia da polimerase com iniciadores específicos de sequência usando o kit One Lambda Inc., Canoga Park, CA, EUA. Resultados: Os pacientes com alelo HLA-DQA1*04:01 apresentaram carga de lesão (ajustada para idade, sexo e duração da EM) acima da mediana em comparação com outros pacientes com demais alelos HLA-DQA1 (p=0,02). Não houve diferenças entre todos os outros alelos HLA e polimorfismos de nucleotídeo único e carga lesional. Conclusões: A correlação do alelo HLA-DQA1*04:01 com maior carga de lesão nas sequências de RM em T2 sugere que a presença desse alelo pode estar associada ao risco de maior gravidade da EM.

Distribution of HLA-DRB1 alleles in BRICS countries with a high tuberculosis burden: a systematic review and meta-analysis

Abstract INTRODUCTION: Tuberculosis (TB) is the leading cause of death worldwide caused by a single infectious disease agent. Brazil, Russia, India, China, and South Africa (BRICS) account for more than half of the world's TB cases. Bacillus Calmette-Guérin (BCG) remains the only vaccine available despite its variable efficacy. Promising antigen-based vaccines have been proposed as prophylactic and/or immunotherapeutic approaches to boost BCG vaccination. Relevant antigens must interact with the range of human leukocyte antigen (HLA) molecules present in target populations; yet this information is currently not available. METHODS: MEDLINE and EMBASE were systematically searched for articles published during 2013-2020 to measure the allelic frequencies of HLA-DRB1 in the BRICS. RESULTS: In total, 67 articles involving 3,207,861 healthy individuals were included in the meta-analysis. HLA-DRB1 alleles *03, *04, *07, *11, *13, and *15 were consistently identified at high frequencies across the BRICS, with a combined estimated frequency varying from 52% to 80%. HLA-DRB1 alleles *01, *08, *09, *10, *12, and *14 were found to be relevant in only one or two BRICS populations. CONCLUSIONS: By combining these alleles, it is possible to ensure at least 80% coverage throughout the BRICS populations.

Polimorfismos do gene HLA-DRB1 em pacientes pediátricos com hepatite autoimune tipo 1 e hepatite autoimune associada à colangite autoimune / Hla-drb1 gene polymorphisms in pediatric patients with type 1 autoimmune hepatitis and type 1 autoimmune hepatitis overlap syndrome with autoimmune cholangitis

ABSTRACT BACKGROUND: Autoimmune hepatitis (AIH) is a rare chronic inflammatory liver disease associated with a loss of immunological tolerance to self-antigens. Susceptibility to AIH is partially determined by the presence of genes related to human leukocyte antigen (HLA), mainly allelic variants of DRB1. OBJECTIVE: The purpose of this study was to investigate the frequencies of the polymorphisms in HLA-DRB1 gene in children and adolescents with type 1 AIH and type 1 AIH overlap syndrome with autoimmune cholangitis (overlap syndrome, OS) in comparison to healthy sex and age-matched individuals (control group). METHODS: This is a cross-sectional study of 25 pediatric patients diagnosed with type 1 AIH and 18 with OS. Fifty-seven healthy individuals were included as controls. The polymorphisms of the HLA-DRB1 gene were evaluated by PCR and included HLA-DRB1*03, HLA-DRB1*04, HLA-DRB1*07, and HLA-DRB1*13. RESULTS: Our results showed that the presence of the allele HLA-DRB1*13 increased the chance of autoimmune cholangitis (OR=3.96, CI 1.07 to 14.61, P=0.04). The HLA-DRB1*04 and HLA- DRB1*07 have no association with the AIH and autoimmune cholangitis in a young sample. CONCLUSION: This work demonstrates an association of the main polymorphisms in the HLA-DRB1 gene to AIH with or without cholangitis in a Brazilian sample.

RESUMO CONTEXTO: Hepatite autoimune (HAI) é uma doença hepática inflamatória crônica, rara, associada à perda da tolerância imunológica aos auto-antígenos. A susceptibilidade à HAI é parcialmente determinada pela presença de genes relacionados ao antígeno leucocitário humano (HLA), principalmente variantes alélicas do DRB1. OBJETIVO: O objetivo deste estudo foi investigar a frequência de polimorfismos no gene HLA-DRB1 em crianças e adolescentes com HAI tipo 1 e HAI tipo 1 associada à colangite autoimune, em comparação com indivíduos saudáveis pareados por sexo e idade (grupo controle). MÉTODOS: Este é um estudo transversal de 25 pacientes pediátricos com diagnóstico de HAI tipo 1 e 18 com HAI associada à colangite autoimune. Cinquenta e sete indivíduos saudáveis foram incluídos como controles. Os polimorfismos do gene HLA-DRB1 foram avaliados por PCR e incluíram HLA-DRB1*03, HLA-DRB1*04, HLA-DRB1*07 e HLA-DRB1*13. RESULTADOS: Nossos resultados mostraram que a presença do alelo HLA-DRB1*13 aumentou a chance de colangite autoimune (OR=3,96; IC 1,07 a 14,61; P=0,04). O HLA-DRB1*04 e o HLA-DRB1*07 não apresentam associação com a HAI e colangite autoimune no grupo de pacientes mais jovens. CONCLUSÃO: Este trabalho demonstra uma associação dos principais polimorfismos no gene HLA-DRB1 à HAI com ou sem colangite na população brasileira.

Associação entre esclerose múltipla e alelos HLA-DRB1 em uma população miscigenada de Salvador, Ba, Brasil / Association between multiple sclerosis and HLA-DRB1 alleles in an admixed population of Salvador, Ba, Brazil

Introdução: a esclerose múltipla é uma doença que afeta preferencialmente o sistema nervoso central de mulheres jovens, causandolhes graus variáveis de incapacidades física e cognitiva. Etiologicamente associa fatores ambientais, biológicos, sócio-econômicos e genéticos, como por exemplo genes do MHC classe II, especialmente os alelos HLA-DRB1*. Objetivo: determinar a frequência dos alelos HLA DRB1* em portadores de esclerose múltipla atendidos no centro de referência do C.H.U.P.E.S, UFBA, no período de outubro de 2014 a abril de 2015 e associá-las a variáveis clínico-demográficas. Metodologia: estudo do tipo caso-controle, aprovado pelo comitê de ética da Faculdade de medicina da Universidade Federal da Bahia (CAAE: 3517134.0.0000.5577), que envolveu uma amostra de conveniência composta por 97 indivíduos, cujos dados clínico-demográficos foram coletados através de questionário desenvolvido para a pesquisa. A genotipagem dos alelos HLA-DRB1* foi realizada através da técnica HLA-DR SSO GenotypingTest. Resultados: a análise quantitativa revelou perfil genotípico do tipo HLA-DRB1*15 (20,5%), em mulheres (83,0%), das raças/etnias negra ou parda (75,0%), com faixa etária entre 30 e 39 anos (28,0%). Houve predomínio da forma clínica surtoremissiva da doença (76,0%), dentre os doentes com idade mais avançada (55,0%), sem permanência de sequela clínica (70,0%) e que usavam algum tipo de Interferon (58,0%). A análise qualitativa indicou maiores frequências, na forma progressiva de esclerose múltipla dos grupos alélicos HLA-DRB1*12 (22,0%), e dos alelos HLA-DRB1*13 (12,6%)e HLA-DRB1*15 (22,0%) naqueles indivíduos com a forma surtoremissiva. Negros e pardos demonstraram maior prevalência do alelo HLA-DRB1*15 (24,0%), enquanto que nos brancos houve maior prevalência do alelo HLA-DRB1*07 (20,0%). Conclusão: forte associação entre as frequências alélicas, esclerose múltipla e as variáveis raça/etnia e forma clínica da doença.

Asociación genética entre los Loci HLA-DRB1 y HLA-DQB1 con la susceptibilidad a padecer Lupus eritematoso sistemático / Genetic association between the Loci HLA-DRB1 and HLA-DQB1 with susceptibility to suffer from systemic lupus erythematosus

La investigación en Inmunogenética brinda información acerca de marcadores genéticos asociados con enfermedades autoinmunes, como el Lupus Eritematoso Sistémico (LES), se puede observar entonces ciertos factores de riesgo o protección hacia la enfermedad en una población determinada. OBJETIVO: Determinar la asociación genética entre los polimorfismos del Complejo Principal de Histocompatibilidad (CPH) representados por los loci HLA-DRB1 y HLA-DQB1 con la susceptibilidad a LES. METODOLOGÍA: Se trabajó con 85 pacientes lúpicos y 85 pacientes sin la enfermedad; se obtuvo DNA humano a partir de sangre periférica, se realizó un PCR-SSP de baja y alta resolución para tipificar molecularmente a los loci HLA-DRB1 y HLA-DQB1. Se determinó las frecuencias alélicas, las cuales fueron asociadas con ambas muestras mediante el uso del Odds Ratio, a un nivel de significancia del 5 %. RESULTADOS: Los resultados del PCR-SSP de baja resolución muestran que ningún alelo HLA tiene un rol predisponente, se observó que el alelo HLA-DRB1*04 presenta un rol protector OR=0,49 (p=0,03). Los resultados por PCR-SSP de alta resolución muestran que los alelos HLA-DRB1*03:01 (OR=18,3; p=0,007), DRB1*04:04 (OR=4,2; p=0,009), DRB1*09:01 (OR=18,3; p=0,007), HLA-QB1*03:03 (OR=18,8; p=0,006) y DQB1*02:01 (OR=21,2; p=0,003) son factores de riesgo. Se evidenció que los alelos HLA-DRB1*08:02 (OR=0,42; p=0,003) y HLA-DQB1*04:02 (OR=0,50; p=0,02) son de carácter protector. CONCLUSIONES: Los alelos que representan riesgo de padecer LES en la muestra estudiada son HLA-DRB1*03:01, 04:04, 09:01 y HLA-DQB1*03:03, 02:01. Los alelos que tiene un carácter protector a la enfermedad son HLA-DRB1*08:02 y HLA-DQB1*04:02.

Immunogenetics research provides information on genetic markers associated with autoimmune diseases such as systemic lupus erythematosus (SLE), you can then observe certain risk factors or protection to the disease in a given population. To determine the genetic association between polymorphisms of the Major istocompatibility Complex loci represented by the HLA-DRB1 and HLA-DQB1 with susceptibility to SLE. METHODOLOGY: We worked with 85 lupus patients and 85 patients without the disease; Human DNA was obtained from peripheral blood, PCR-SSP low and high resolution molecularly performed to establish the loci HLA-DRB1 and HLA-DQB1. Allele frequencies, which were associated with both samples using the Odds Ratio at a level of significance of 5% were determined. RESULTS: Results of PCR-SSP low-resolution HLA show that no predisposing allele plays a role, we observed that HLA-DRB1*04 allele has a protective role OR=0.49 (p=0.03). The PCR-SSP results of high resolution show that the HLA-DRB1*03:01 alleles (OR=18.3; p=0.007), DRB1*04:04 (OR=4.2; p=0.009), DRB1*09:01 (OR=18.3; p=0.007), HLA-QB1*03:03 (OR=18.8; p=0.006) and DQB1*02:01 (OR=21.2; p=0.003) are risk factors. We demonstrated that HLA-DRB1*08:02 alleles (OR=0.42; p=0.003) and HLA-QB1*04:02 (OR=0.50; p=0.02) are of a protective nature. CONCLUSIONS: The alleles representing LES risk in the study sample are HLA-DRB1*03:01, *04:04, *09:01 and HLA-DQB1*03:03, *02:01. The alleles having a protective character to the disease are HLADRB1* 08:02 and HLA-DQB1*04:02.

Human leukocyte antigen HLADRB1 determinants susceptibility to gastroesophageal reflux disease / Antígeno leucocitário humano HLADRB1 é determinante de susceptibilidade para a doença do refluxo

ABSTRACT BACKGROUND Gastroesophageal reflux disease (GERD) is characterized by diverse symptoms. There is an evidence for a genetic component to GERD as supported by familial aggregation of this disease. OBJECTIVE To investigate whether certain human leucocyte antigen genes HLA-DRB1 are associated with GERD. METHODS Patients and controls were prospectively recruited from GIT center at Al-Kindy Teaching Hospital (Baghdad-Iraq) between January 2014 and July 2016. Sixty Iraqi Arab Muslims patients with a history of heartburn and dyspepsia compared with 100 Iraqi Arab Muslims controls. All study patients and control groups underwent upper gastrointestinal endoscopic examinations and their serums were analyzed for CagA antibodies Immunoglobulin G (IgG) for H. pylori. HLA-DRB1 genotyping were done to both groups. RESULTS A total of 60 patients with erosive gastritis; GERD (Grade II and III) were evaluated, together with 100 controls. There is a significant increase of H. pylori infection (P=0.0001) in GERD patients than control group. HLA-DRB1* 15:01 was significantly increased in GERD patients in comparison with control group and an increased frequency of HLADRB1*11:01 in control group compared with patients group. CONCLUSION There is an association between HLA-DRB1 *15:01 in GERD patients with H. pylori positive patients.

RESUMO CONTEXTO A doença do refluxo gastroesofágico (DRGE) caracteriza-se por diversos sintomas. Há evidências de um componente genético para a doença de refluxo suportado pela agregação familiar desta doença. OBJETIVO Investigar se certos genes de antígeno de leucócito humano HLA-DRB1 são associados à DRGE. MÉTODOS Pacientes e indivíduos controles foram recrutados prospectivamente do centro GIT no Al-Kindy Hospital (Bagdá-Iraque) entre de 2014 janeiro e julho de 2016. Sessenta pacientes muçulmanos árabes iraquianos com uma história de azia e dispepsia foram comparados com 100 indivíduos controles. Todos os pacientes do estudo e grupos de controle foram submetidos a exames de endoscopia gastrointestinal alta e seus soros foram analisados para anticorpos CagA imunoglobulina G (IgG) para H. pylori. Genotipagem HLA-DRB1 foram feitas para ambos os grupos. RESULTADOS Um total de 60 pacientes com gastrite erosiva; GERD (grau II e III) foram avaliados, em conjunto com 100 controles. Houve aumento significativo de infecção pelo H. pylori (P=0,0001) em pacientes com DRGE em relação ao grupo controle. O HLA-DRB1* 15:01 aumentou significativamente em pacientes com DRGE em comparação com o grupo controle e houve uma maior frequência de HLADRB1* 11:01 no grupo controle em comparação com o grupo de pacientes com DRGE. CONCLUSÃO Há uma associação entre HLA-DRB1* 15:01 em pacientes com DRGE positivos para a infecção por H. pylori.

Lack of association between alopecia areata and HLA class I and II in a southeastern Brazilian population

Abstract: Background: Alopecia areata (AA) is a common disorder of unknown etiology that affects approximately 0.7% to 3.8% of patients among the general population. Currently, genetic and autoimmune factors are emphasized as etiopathogenic. Studies linking Human Leukocyte Antigens (HLA) to AA have suggested that immunogenetic factors may play a role in the disease's onset/development. Objectives: To investigate an association between AA and HLA class I/II in white Brazilians. Methods: Patients and control groups comprised 33 and 112 individuals, respectively. DNA extraction was performed by column method with BioPur kit. Allele's classification was undertaken using the PCR-SSO technique. HLA frequencies were obtained through direct counting and subjected to comparison by means of the chi-square test. Results: Most patients were aged over 16, with no familial history, and developed partial AA, with no recurrent episodes. Patients showed a higher frequency of HLA-B*40, HLA-B*45, HLA-B*53 and HLA-C*04 compared with controls, although P was not significant after Bonferroni correction. Regarding HLA class II, only HLA-DRB1*07 revealed statistical significance; nevertheless, it featured more prominently in controls than patients (P=0.04; Pc=0.52; OR=0.29; 95%; CI=0.07 to 1.25). P was not significant after Bonferroni correction. Conclusions: The development of AA does not seem to be associated with HLA in white Brazilians, nor with susceptibility or resistance. The studies were carried out in populations with little or no miscegenation, unlike the Brazilian population in general, which could explain the inconsistency found.

Associação de alelos HLA e aborto espontâneo recorrente em uma população de São Luís/Maranhão, na região Nordeste do Brasil / HLA alleles association and recurrent spontaneous abortion in a São Luis/Maranhão population, in Brazilian Northeastern region

Investigar a associação dos alelos HLA-A, -B e -DRB1 com a ocorrência de Aborto Espontâneo Recorrente.

The role of KIR2DL3/HLA-C*0802 in Brazilian patients with rheumatoid vasculitis

OBJECTIVES: Rheumatoid arthritis is a polygenically controlled systemic autoimmune disease. Rheumatoid vasculitis is an important extra-articular phenotype of rheumatoid arthritis that can result in deep cutaneous ulcers. The objective of this study was to establish a correlation between the frequency of major histocompatibility complex class I/II alleles and killer immunoglobulin-like receptor genotypes in patients with cutaneous rheumatoid vasculitis. METHODS: Using the Scott & Bacon 1984 criteria to diagnose rheumatoid vasculitis and after excluding any other causes such as diabetes, atherosclerosis, adverse drug reactions, infection, and smoking, patients who met the criteria were selected. All of the selected rheumatoid vasculitis patients presented deep cutaneous ulcers. Identification of the major histocompatibility complex class I/II and killer immunoglobulin-like receptor genotypes was performed by polymerase chain reaction assays of samples collected from the 23 rheumatoid vasculitis patients as well as from 80 controls (40 non-rheumatoid vasculitis RA control patients and 40 healthy volunteers). RESULTS: An association between the presence of the HLA-DRB1*1402 and HLA-DRB1*0101 alleles and cutaneous lesions in rheumatoid vasculitis patients and a correlation between the inhibitor KIR2DL3 and the HLA-C*0802 ligand in rheumatoid vasculitis patients were found. CONCLUSION: An association was found between the presence of the HLA-DRB1*1402 and HLA-DRB1*0101 alleles and the development of cutaneous lesions in rheumatoid vasculitis patients. Additionally, the HLA-C*0802 ligand protects these individuals from developing cutaneous lesions. .

The CIITA genetic polymorphism rs4774*C in combination with the HLA-DRB1*15:01 allele as a putative susceptibility factor to multiple sclerosis in Brazilian females / O polimorfismo rs4774*C no gene CIITA em conjunção com o alelo HLA-DRB1*15:01 é um possível fator de susceptibilidade a esclerose múltipla em mulheres brasileiras

The objective of this study was to investigate the association between the HLA alleles at the DQA1, DQB1 and DRB1 loci, the CIITA genetic polymorphisms -168A/G and +1614G/C, and susceptibility to multiple sclerosis (MS) in a sample from Rio de Janeiro State, Brazil. Furthermore, we wished to determine whether any of these associations might be more significant in women compared with men. DNA samples from 52 relapsing-remitting MS (RRMS) patients and 126 healthy controls matched for sex and age were analyzed. We identified a significant HLA-DRB1*15:01-MS association that was female-specific (Odds Ratio (OR) = 4.78; p = 0.001). Furthermore, we observed that the +1614G/C mutation in combination with the HLA-DRB1*15:01 allele increased susceptibility to MS in females (OR = 4.55; p = 0.01). Together, these findings highlight the polygenic nature of MS.

O objetivo deste estudo foi investigar a associação entre alelos HLA, loci DQA1, DQB1 e DRB1, polimorfismos -168A/G e +1614G/C no gene CIITA, e suscetibilidade à esclerose múltipla (EM) em uma amostra de Rio de Janeiro, Brasil. Além disso, buscou-se determinar se alguma dessas associações pode ser gênero-dependente. Foram analisadas amostras de DNA de 52 pacientes com EM reincidente-remitente (EMRR) e 126 controles saudáveis ​​pareados por sexo e idade. Foi identificada associação significativa HLA-DRB1*15:01-EMRR, que foi específica para o gênero feminino (Odds Ratio (OR) = 4,78, p = 0,001). Além disso, observou-se que o polimorfismo +1614 G/C, em combinação com o alelo HLA-DRB1*15:01 provoca o aumento da susceptibilidade à EM em pacientes do sexo feminino (OR = 4,55, p = 0,01). Juntos, estes resultados destacam a natureza poligênica da EM.

Rio Grande do Norte, Brazil, voluntary bone marrow donors registry analysis / Análise do registro de doadores voluntários de medula óssea do Rio Grande do Norte, Brasil.

Objective: this study aimed to report the allele and haplotype frequencies of volunteer bone marrow donors (VBMD) from the state of Rio Grande do Norte (RN) who were enrolled in the Brazilian Volunteer Bone Marrow Donor Registry (REDOME). Methods: the sample comprised 12,973 VBMD who had their allele and haplotype frequencies calculated by Arlequin 3.5.1.2. A multivariate analysis of the data was obtained through a principal component analysis (PCA) and hierarchical cluster analysis (HCA) performed with SPSS 8.0. Results: the most frequent allelic group was HLA-A*02, followed by -DRB1*13, -DRB1*04, -DRB1*07, -B*44, -B*35, -A*24 and -DRB1*01. Of the 2,701 haplotypes observed, the three most frequent were HLA-A*01 B*08 DRB1*03 (1.62%), -A*29 B*44 DRB1*07 (1.56%) and -A*02 B*44 DRB1*04 (1.29%). These haplotypes were in linkage disequilibrium. RN allele and haplotype frequencies were very similar to those in other Brazilian states in which similar studies have been performed. The PCA revealed that RN is highly genetically similar to Caucasian populations, especially those from Iberian countries, which strongly influenced the state’s ethnic composition. Africans and Amerindians also influenced the RN population structure, to a lesser extent. Conclusion: the HCA reinforced the conclusion that, despite its highly admixed profile, the RN population is genetically similar to European and European-descended populations. The PCA also showed that RN cities do not contribute to the same extent to REDOME, with less populous cities being underrepresented, indicating the need to enroll more VBMD from these smaller cities to faithfully depict the state’s population structure in the database. .

Objetivo: relatar as frequências alélicas e haplotípicas do HLA-A, -B e -DRB1 de doadores voluntários de medula óssea (DVMO) do Rio Grande do Norte (RN), inscritos no Registro Nacional de Doadores de Medula Óssea (REDOME). Metodologia: 12.973 DVMO tiveram suas frequências alélica e haplotípica calculadas pelo programa Arlequin 3.5.1.2. Uma análise multivariada dos dados foi obtida por meio da Análise de Componente Principal (ACP) e da Análise de Cluster Hierárquico (ACH) realizadas pelo SPSS 8.0. Resultados: os grupos alélicos mais frequentes foram HLA-A*02, seguido por -DRB1*13, -DRB1*04, -DRB1*07, -B*44, -B*35, -A*24 e -DRB1*01. Dos 2.701 haplótipos observados, os três mais frequentes foram HLA-A*01 B*08 DRB1*03 (1,62%), -A*29 B*44 DRB1*07 (1,56%) e -A*02 B*44 DRB1*04 (1,29%), que se encontravam em desequilíbrio de ligação. As frequências alélicas e haplotípicas do RN são bastante similares às de outros estados brasileiros em que trabalhos semelhantes foram executados. A ACP revelou ser o RN geneticamente muito semelhante a populações caucasianas, especialmente a dos países ibéricos, os quais influenciaram fortemente na composição étnica do Estado. Africanos e ameríndios também contribuíram para a estrutura populacional, mas em menor proporção. Conclusão: a ACH reforçou a conclusão de que, apesar de seu perfil miscigenado, a população do RN se assemelha geneticamente com populações europeias e que descendem das europeias. A ACP também mostrou que as cidades do RN não contribuem equitativamente na composição do REDOME, de modo que cidades pouco populosas estão sub-representadas, apontando a necessidade de cadastrar mais DVMO dessas cidades para que a estrutura da população seja fielmente retratada. .

Impact of Light Salt Substitution for Regular Salt on Blood Pressure of Hypertensive Patients / Impacto da Substituição de Sal Comum por Sal Light sobre a Pressão Arterial de Pacientes Hipertensos

Background: Studies have shown sodium restriction to have a beneficial effect on blood pressure (BP) of hypertensive patients. Objective: To evaluate the impact of light salt substitution for regular salt on BP of hypertensive patients. Methods: Uncontrolled hypertensive patients of both sexes, 20 to 65 years-old, on stable doses of antihypertensive drugs were randomized into Intervention Group (IG - receiving light salt) and Control Group (CG - receiving regular salt). Systolic BP (SBP) and diastolic BP (DBP) were analyzed by using casual BP measurements and Home Blood Pressure Monitoring (HBPM), and sodium and potassium excretion was assessed on 24-hour urine samples. The patients received 3 g of salt for daily consumption for 4 weeks. Results: The study evaluated 35 patients (65.7% women), 19 allocated to the IG and 16 to the CG. The mean age was 55.5 ± 7.4 years. Most participants had completed the Brazilian middle school (up to the 8th grade; n = 28; 80.0%), had a family income of up to US$ 600 (n = 17; 48.6%) and practiced regular physical activity (n = 19; 54.3%). Two patients (5.7%) were smokers and 40.0% consumed alcohol regularly (n = 14). The IG showed a significant reduction in both SBP and DBP on the casual measurements and HBPM (p < 0.05) and in sodium excretion (p = 0.016). The CG showed a significant reduction only in casual SBP (p = 0.032). Conclusions: The light salt substitution for regular salt significantly reduced BP of hypertensive patients. .

Fundamento: Alguns estudos demostraram um efeito benéfico da restrição de sódio na pressão arterial (PA) de hipertensos. Objetivo: Avaliar o impacto da substituição do sal comum por sal light na PA de hipertensos. Métodos: Hipertensos não controlados, de ambos os sexos, com idades entre 20 e 65 anos, e usando doses estáveis de anti-hipertensivos foram randomizados para um Grupo Intervenção (GI - recebendo sal light) e um Grupo Controle (GC - recebendo sal comum). A PA sistólica (PAS) e a PA diastólica (PAD) foram analisadas usando-se medidas casuais da PA e Monitoração Residencial da Pressão Arterial (MRPA), e a excreção de sódio e potássio foi avaliada em amostras de urina de 24 horas. Os pacientes receberam 3 g de sal para consumo diário por 4 semanas. Resultados: Este estudo avaliou 35 pacientes (65,7% mulheres), 19 alocados no GI e 16 no GC. A idade média foi de 55,5 ± 7,4 anos. A maioria dos participantes havia completado o ensino fundamental (até a 8a série; n = 28; 80,0%), tinha renda familiar de até dois salários mínimos (n = 17; 48,6%) e praticava atividade física regularmente (n = 19; 54,3%). Dois pacientes (5,7%) eram fumantes e 40,0% consumiam álcool com regularidade (n = 14). O GI mostrou uma significativa redução tanto da PAS quanto da PAD nas medidas casuais e de MRPA (p < 0,05) e, ainda, diminuição da excreção de sódio (p = 0,016). O GC apresentou redução significativa apenas na medida casual da PAS (p = 0,032). Conclusões: A substituição do sal comum por sal light diminuiu significativamente a PA de hipertensos. .

Genetic diversity among volunteer donors of bone marrow in southeastern Brazil, according to the HLA system / Diversidade genética entre doadores voluntários de medula óssea no sudeste do Brasil, segundo o sistema HLA

CONTEXT AND OBJECTIVE: Checking the histocompatibility of the molecules of the human leukocyte antigen (HLA) system is vital for performing bone marrow transplantation with allogeneic material. The objective of this study was to characterize bone marrow donors according to gender, age, ethnicity and HLA groups at a regional hemotherapy center in Brazil. DESIGN AND SETTING: Descriptive study on registered donors at a regional hemotherapy center in a public university hospital in the southeastern region of Brazil. METHODS: The records of 66,780 donors who were registered between 2005 and June 2011 were consulted, and the variables studied were tabulated. RESULTS: There were equal numbers of male and female donors and 82.8% of them were under 45 years of age. In terms of ethnicity, 77.3% declared themselves to be white, 15.0% mixed race, 5.7% black and 2% others. In terms of immunogenetic characterization, the most frequent HLA-A allelic group was HLA-A*02, with 39.20% of the donors; in the HLA-B allelic group, the most common was HLA-B*35, with 14.18%; while in the HLA-DRB1 allelic group, the most frequent was HLA-DRB1*03, with 17.03%. Comparison between these results and data from the Brazilian Bone Marrow Donor Registry (REDOME) showed that there were demographic and immunogenetic differences due to the history of immigration in the region of Ribeirão Preto, in southeastern Brazil. CONCLUSIONS: The results reinforce the importance of understanding the demographic and immunogenic profile of regions of Brazil, in order to reduce the waiting time for a histocompatible donor. .

CONTEXTO E OBJETIVO: Para a realização de transplantes de medula óssea com material alogênico, é necessária a verificação de histocompatibilidade das moléculas do sistema HLA (human leukocyte antigen), fundamental para o sucesso desses transplantes. O objetivo desta pesquisa foi caracterizar os doadores de medula óssea segundo gênero, idade, etnia e grupos HLA de um centro regional de hemoterapia brasileiro. TIPO DE ESTUDO E LOCAL: Estudo descritivo dos doadores cadastrados em um centro regional de hemoterapia de um hospital público universitário da região Sudeste do Brasil. MÉTODOS: Foram consultadas as fichas dos 66.780 doadores cadastrados entre 2005 e junho de 2011 e tabuladas as variáveis estudadas. RESULTADOS: Encontrou-se distribuição equilibrada entre os gêneros, e 82,8% dos doadores tinham até 45 anos de idade. Quanto à etnia auto-referida, 77,3% se apresentaram como brancos, 15,0% como pardos, 5,7% como negros, os 2% restantes dividindo-se em outras etnias. Quanto à caracterização imunogenética, no grupo alélico HLA-A, o mais frequente foi o HLA-A*02, com 39,20%; no grupo alélico HLA-B, o mais comum foi o HLA-B*35, com 14,18%; no grupo alélico HLA-DRB1, o mais frequente foi o HLA-DRB1*03, com 17,03% do total de doadores. Quando esses resultados são comparados com os dados do cadastro nacional de doadores (REDOME), observam-se diferenças demográficas e imunogenéticas, que se explicam pelo histórico de imigração da região de Ribeirão Preto, no Sudeste brasileiro. CONCLUSÕES: Os resultados encontrados reforçam a importância de conhecer o perfil demográfico e imunogenético das regiões do Brasil, para reduzir o tempo de espera por um doador histocompatível. .

Alta frecuencia de DQ8 en la población celiaca de la provincia del Chaco, Argentina / [High frequency of DQ8 in the celiac population of Chaco province, Argentina].

BACKGROUND: There is a strong association between celiac disease (CD) and certain genes of the major histocompatibility complex (HLA). The CD specifically related alleles are those coding for HLA-DQ2 heterodimer and to a lesser degree for HLA-DQ8. OBJECTVE. The aim of this study was to evaluate the frequency of HLA-DQB1* and HLA-DRB1* alleles, haplotypes, and genotypes in patients diagnosed with CD and in control population of Chaco, in order to establish its distribution and compare it with that observed in other populations. METHODS: A total of 139 samples from patients diagnosed with CD and 119 healthy controls were typed for HLA-DQ and HLA-DR, using PCR and reverse hybridization (INNO-LiPA or Dynal). RESULTS: Comparing patients with CD vs. controls, the DQBI*0201 (P = 0.0002), DQBJ*0202 (P = 0.0046), DQBI*0302 (P = 0. 0006), DRBl *03 (P = 0.0002), DRBl *04 (P = 0.0199) and DRB1 *07 (P = 0.0062) were significantly increased, while a decrease was observed in HLA-DQB1*0301 (P = 0.0006), HLA-DQBI*0303 (P = 0.0070), DQBI*0501 (P = 0.0023), DQB1*0604 (P = 0.0140) DRB1*01 (P = 0.0023), DRB1*08 (P = 0.0165), DRB1*09 (P = 0.0362) and DRB1*16 (P = 0.0228). Within DQB1* genotypes associated with EC, 65.4

of patients had the DQB1*02 in linkage disequilibrium with DRB1*03 or DRB1*07 (DQ2), and 43.2

presented genotype DQB1*0302 in linkage disequilibrium with DRB1*04 (DQ8). Both genotypes were shared by 15.2

of them. CONCLUSIONS: We point out the high frequency of DQ8 associated with CD. Although the DQ2 is still the most common, this finding could be attributed to the Amerindian influence in our population.

Associação do alelo HLA-DRB1 com suscetibilidade a artrite reumatoide e gravidade da doença na Síria / HLA-DRB1 allele association with rheumatoid arthritis susceptibility and severity in Syria

INTRODUÇÃO: A artrite reumatoide (AR) é uma doença crônica multifatorial complexa. A importância do sistema de antígenos leucocitários humanos (HLA) como fator significativo de risco genético para AR foi estudada no mundo. Embora amplamente distribuídos em diferentes áreas na Síria, faltam estudos sobre o papel dos HLA. OBJETIVO: O objetivo de nosso estudo foi determinar a associação dos alelos HLA-DRB1 com a suscetibilidade a AR e sua gravidade na Síria. PACIENTES E MÉTODOS: Foram genotipados 86 pacientes com AR e 200 controles normais, usando-se reação em cadeia da polimerase com sequência de primer específico (PCR-SSP). Anticorpos anti-CCP foram determinados por ELISA. Fator reumatoide (FR), proteína C-reativa (PCR), velocidade de hemossedimentação (VHS) e o índice de atividade da doença (DAS-28) foram obtidos nos registros médicos e utilizados para avaliar a gravidade clínica dos pacientes. RESULTADOS: Os alelos HLA-DRB1 *01, *04 e *10 mostraram forte associação com suscetibilidade à doença (OR = 2,29, IC 95% = 1,11-4,75, P = 0,022; OR = 3,16, IC 95% = 2,08-4,8, P < 0,0001; e OR = 2,43, IC 95% = 1,07-5,51, P = 0,029, respectivamente), enquanto a frequência dos alelos HLA-DRB1 *11 e *13 foi significativamente mais baixa nos pacientes com AR do que nos controles (OR = 0,49, IC 95% = 0,3-0,8, P = 0,004; OR = 0,32, IC 95% = 0,15-0,69, P = 0,002, respectivamente). Os outros alelos HLA-DRB1 mostraram diferença significativa. A frequência dos anticorpos anti-CCP foi maior em pacientes epítopo compartilhado (EC) positivos do que em pacientes EC-negativos (OR = 5,5, IC 95% = 2-15,1, P = 0,00054). O índice DAS-28 de pacientes com AR não mostrou diferença significativa entre os grupos EC-negativo e EC-positivo. CONCLUSÃO: Nossos resultados indicam que os alelos HLA-DRB1 *01, *04 e *10 estão relacionados com AR, enquanto os alelos HLA-DRB1 *11 e *13 protegem a população síria contra a AR.

INTRODUCTION: Rheumatoid arthritis (RA) is a complex multifactorial chronic disease. The importance of human leukocyte antigen as a major genetic risk factor for RA was studied worldwide. Although it is widely distributed in different Syrian areas, studies of human leukocyte antigen (HLA) alleles' role are absent. OBJECTIVE: The aim of our study was to determine the association of HLA-DRB1 alleles with the susceptibility and severity of RA in Syria. PATIENTS AND METHODS: Eightysix RA patients and 200 healthy controls from Syria were genotyped using polymerase chain reaction with sequencespecific primer (PCR-SSP). Anti-CCP antibodies were measured by ELISA. Rheumatoid factor (RF), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and disease activity score 28 (DAS-28) values were obtained from patients' medical records. DAS-28 was used to assess the clinical severity of the patients. RESULTS: The HLA-DRB1*01, *04, and *10 frequencies showed a strong association with the disease susceptibility (OR = 2.29, 95% CI = 1.11-4.75, P = 0.022; OR = 3.16, 95% CI = 2.0 -4.8, P < 0.0001; OR = 2.43, 95% CI = 1.07-5.51, P = 0.029 respectively), while the frequencies of HLA-DRB1*11, and *13 were signifi cantly lower in RA patients than in controls (OR = 0.49, 95% CI = 0.3-0.8, P = 0.004; OR = 0.32, 95% CI = 0.15-0.69, P = 0.002, respectively). The other HLA-DRB1 alleles showed no signifi cant difference. The frequency of anti-CCP antibodies was higher in shared epitope (SE) positive patients compared with SE-negative patients (OR = 5.5, 95% CI = 2-15.1, P = 0.00054). DAS-28 of RA patients didn't show signifi cant difference between the SE negative and the SE positive groups. CONCLUSION: Our results indicate that HLA-DRB1*01, *04, and *10 alleles are related with RA, while HLA-DRB1*11 and *13 protect against RA in the Syrian population.

Association analysis of human leukocyte antigen class II (DRB1) alleles with leprosy in individuals from São Luís, state of Maranhão, Brazil

Epidemiological studies have demonstrated that the variability of the clinical response to infection caused by Mycobacterium leprae is associated with host genetic factors. The present study investigated the frequency of human leukocyte antigen (HLA) class II (DRB1) alleles in patients with leprosy from São Luís, Maranhão, Brazil. A case-control study was performed in 85 individuals with leprosy and 85 healthy subjects. All samples were analysed via polymerase chain reaction-sequence specific oligonucleotide probes. The HLA-DRB1*16 allele showed a higher frequency in the group with leprosy [(9.41% vs. 4.12%) odds ratio (OR) = 2.41 95% confidence interval (CI) (0.96-6.08) p = 0.05], whereas the HLA-DRB1*11 allele was less frequent in the group with leprosy [(6.47% vs. 11.76%) OR = 0.51 95% CI (0.23-1.12) p = 0.09]. The frequency of HLA-DRB1* alleles between the control group and leprosy patient subgroups presenting different forms of the disease showed that the HLA-DRB1*16 (16.13% vs. 8.24%, OR = 4.10, CI = 1.27-13.27, p = 0.010) and HLA-DRB1*14 (5% vs. 3.53%, OR = 4.63, CI = 1.00-21.08, p = 0.032) alleles were significantly more frequent in patients with different clinical subtypes of leprosy. The sample size was a limitation in this study. Nevertheless, the results demonstrated the existence of a genetic susceptibility associated with the clinical forms of leprosy. The low frequency of the HLA-DRB1*11 allele should be further studied to investigate the possible protective effect of this allele.

Association between HLA-DRB1* polymorphisms and hepatitis B infection in a brazilian population / Associação entre polimorfismos HLA-DRB1* e infecção por hepatite B em uma população brasileira

OBJECTIVE: The aim of the present study was to determine the genotype association for alleles of class II human leukocyte antigens (HLA) in the DRB1* locus among blood donors at the Fundação Hemope (Brazil) infected by or immunized for the hepatitis B virus (HBV). METHODS: A case-control study was performed, comprising a group of individuals infected by HBV and a control group of immunized individuals at a proportion of 1:4. Blood samples were taken for the HLA typing of the DRB1* locus. Univariate and multivariate analyses were performed for the assessment of associations between the categorical variables using the chi-squared test and Fisher's exact test. RESULTS: A total of 320 blood donors were analyzed (241 males [75%] and 79 females [25%] with a mean age of 39 years). The case group consisted of 64 HBV-infected donors and the control group was composed of 256 HBV-immunized donors. The multivariate analysis stratified by gender revealed that the DRB1*09 allele was associated with infected male donors (p = 0.016) and the DRB1*08 allele was associated with infected donors aged 39 years or younger (p = 0.031). CONCLUSION: The results of the present study reveal that younger blood donors and male blood donors who respectively exhibit the DRB1*08 and DRB1*09 alleles are more susceptible to intensification of HBV infection.

OBJETIVO: O objetivo do presente estudo foi determinar a associação genotípica dos alelos de classe II dos antígenos leucocitários humanos (HLA) presentes no locus DRB1* entre doadores de sangue da Fundação Hemope (Brasil), infectados pelo ou imunizados contra o vírus da hepatite B (HBV). MÉTODOS: Estudo caso-controle foi realizado com um grupo de indivíduos infectados pelo HBV e um grupo controle composto de indivíduos imunizados na proporção de 1:4. Amostras de sangue foram coletadas para a tipagem HLA do locus DRB1*. Análises univariada e multivariada foram realizadas para a avaliação de associações entre as variáveis categóricas pelo teste do qui-quadrado e teste exato de Fisher. RESULTADOS: Um total de 320 doadores de sangue foram analisados (241 homens [75%] e 79 do sexo feminino [25%], com idade média de 39 anos). O grupo de casos consistiu de 64 doadores infectados pelo HBV e o grupo controle foi composto de 256 doadores imunes ao HBV. A análise multivariada estratificada por sexo revelou que o alelo DRB1*09 foi associado com os doadores infectados do sexo masculino (p = 0,016) e do alelo DRB1*08 foi associado com os doadores infectados com idade entre 39 anos ou mais jovens (p = 0,031). CONCLUSÃO: Os resultados do presente estudo revelam que doadores de sangue mais jovens e doadores de sangue do sexo masculino que exibem, respectivamente, os alelos DRB1*08 e DRB1*09, são mais suscetíveis à cronificação da infecção pelo HBV.

Frecuencia de alelos HLA de clase I y II en una cohorte de pacientes con espondiloartritis provenientes del noroccidente colombiano / Frequency of HLA alleles class I and II in a cohort of northwestern Colombian patients with spondyloarthritis

Introducción. Las espondiloartritis son enfermedades reumatológicas crónicas que afectan el esqueleto axial y las articulaciones periféricas, con varias manifestaciones extraarticulares. La asociación con el HLA-B27 sigue siendo uno de los vínculos más fuertes conocidos entre estas entidades y el complejo mayor de histocompatibilidad; sin embargo, la distribución mundial del HLA-B27 varía considerablemente y se han descrito asociaciones con genes no HLA-B27. Objetivo. Conocer la frecuencia de alelos HLA de clase I y II en pacientes con espondiloartritis provenientes del noroccidente colombiano y su frecuencia en las manifestaciones clínicas y radiológicas específicas. Materiales y métodos. Se condujo un estudio descriptivo, observacional, de corte transversal, retrospectivo y prospectivo entre 2005 y 2008 de 56 pacientes colombianos con espondiloartritis. Se identificaron los alelos correspondientes a los loci HLA de clase I y II (HLA-B, HLADQB1 y HLADRB). Se analizó su frecuencia con las manifestaciones clínicas axiales, periféricas, extraarticulares y radiológicas. Resultados. Se encontró una baja frecuencia de HLA-B27 en la población total (50 %), aunque fue el alelo más frecuente, junto con HLA-DRB4*01 (35,7 %) y HLA-DQB1*0501 (28,6 %), en todos los pacientes en general y en cada una de las manifestaciones clínicas y radiológicas. Se resalta la alta frecuencia de HLA-B27 y HLA-DRB4*01 (64,3 %) en pacientes con dactilitis, hallazgo novedoso sin previa descripción. Conclusión. Los alelos HLA-B27, HLA-DRB4*01 y HLA-DQB1*0501 fueron frecuentes en los diferentes subtipos de espondiloartritis y en las manifestaciones clínicas axiales, periféricas y extraarticulares específicas, además de la sacroiliítis radiológica.

Introduction. Spondyloarthritis is a chronic rheumatic disease that affect the axial skeleton and peripheral joints, along with several extra-articular manifestations. The association with HLA-B27 remains one of the strongest known links between these entities and the major histocompatibility complex. However, the global distribution of HLA-B27 varies considerably and furthermore, associations with non-HLA-B27 genes have been described. Objective. The frequency of HLA class I and II was determined in a population of patients with spondyloarthritis with respect to detection in the clinical setting and by radiology. Materials and methods. A descriptive, observational, cross-sectional, retrospective and prospective study was conducted in 56 patients from northwestern Colombia. Each was diagnosed with spondyloarthritis between 2005 and 2008. In each case, alleles were identified for the loci HLA class I and II (HLA-B; HLADQB1 and HLADRB). The frequency of these alleles in the axial, peripheral, extraarticular and radiological manifestations. Results.The frequency of HLA-B27 was 50% overall, and it was the most frequent allele. The two other alleles were HLA.DRB4*01 at 35.7% and HLA-DQB1*0501 at 28.6%, as detected in each of the clinical and radiological manifestations. A high frequency of HLA-B27 and HLA-DRB4*01 (64.3%) was noted in patients with dactylitis. Conclusion. The alleles HLA-B27, HLA-DRB4*01 and HLA-DQB1*0501 were common in the different subtypes of spondyloarthritis and were frequent in the specific clinical axial, peripheral and extraarticular clinical manifestations, as well as radiological sacroiliitis.

Use of PCR with Sequence-specific Primers for High-Resolution Human Leukocyte Antigen Typing of Patients with Narcolepsy

BACKGROUND: Narcolepsy is a neurologic disorder characterized by excessive daytime sleepiness, symptoms of abnormal rapid eye movement (REM) sleep, and a strong association with HLA-DRB1*1501, -DQA1*0102, and -DQB1*0602. Here, we investigated the clinico-physical characteristics of Korean patients with narcolepsy, their HLA types, and the clinical utility of high-resolution PCR with sequence-specific primers (PCR-SSP) as a simple typing method for identifying DRB1*15/16, DQA1, and DQB1 alleles. METHODS: The study population consisted of 67 consecutively enrolled patients having unexplained daytime sleepiness and diagnosed narcolepsy based on clinical and neurological findings. Clinical data and the results of the multiple sleep latency test and polysomnography were reviewed, and HLA typing was performed using both high-resolution PCR-SSP and sequence-based typing (SBT). RESULTS: The 44 narcolepsy patients with cataplexy displayed significantly higher frequencies of DRB1*1501 (Pc= 0.003), DQA1*0102 (Pc=0.001), and DQB1*0602 (Pc=0.014) than the patients without cataplexy. Among patients carrying DRB1*1501-DQB1*0602 or DQA1*0102, the frequencies of a mean REM sleep latency of less than 20 min in nocturnal polysomnography and clinical findings, including sleep paralysis and hypnagogic hallucination were significantly higher. SBT and PCR-SSP showed 100% concordance for high-resolution typing of DRB1*15/16 alleles and DQA1 and DQB1 loci. CONCLUSIONS: The clinical characteristics and somnographic findings of narcolepsy patients were associated with specific HLA alleles, including DRB1*1501, DQA1*0102, and DQB1*0602. Application of high-resolution PCR-SSP, a reliable and simple method, for both allele- and locus-specific HLA typing of DRB1*15/16, DQA1, and DQB1 would be useful for characterizing clinical status among subjects with narcolepsy.