DQB1*0602 confers genetic susceptibility to multiple sclerosis in Afro‐Brazilians

Abstract

We studied the distribution of the HLA-DRB1, -DQA1 and -DQB1 alleles in 44 Afro-Brazilian patients with multiple sclerosis and 88 controls. Although no significant differences were found between the patients and controls for the DRB1 and DQA1 alleles, the HLA-DQB1*0602 allele was positively associated with multiple sclerosis (45.0% vs. 17.0%, Pc=0.024, RR=3.31). The positive extended haplotypes for DQB1*0602 were more frequent in patients than controls, although the differences were not statistically significant in any of them. These results in Afro-Brazilians are in line with other studies which have found DQB1*0602 to be associated with the disease in the absence of the DRB1*1501 allele. We therefore think that the association with the disease in this ethnic group is more allelic than haplotypic.

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

“…Unlike previous studies conducted on Brazilian populations 8,24 , we did not observe an association between the HLA-DQA1*02:01-03:01 alleles and MS (Table 3). In addition, an association between HLA-DQB1*06:02 and MS in the absence of DRB1*15:01 was not observed in patients of African descent, which also does not agree with previous studies 10 . These inconsistent results may be due to differences in the ethnic admixtures of the analyzed population samples.…”

“…The fact that such a phenomenon is observed in Brazil could be attributed to the degree of ethnic admixing among the local population 10 . In a recent genome-screening survey, several novel loci were identified that showed significant associations with MS outcome, including IL2RA, IL7RA, CLEC16A, CD58, TNFRSFA1 and IRF8 27 , the majority of which are located near genes with immune functions or that have been associated with other autoimmune diseases.…”

“…Studies performed on North American and European populations revealed an association between the HLA-DRB1*15:01, -DQA1*01:02 and -DQB1*06:02 alleles and the development of MS 7 , and these alleles have also been linked to MS in the Brazilian population 8,9,10 . In particular, a previous Brazilian study showed that the DRB1*15:01 allele confers ethnicity-dependent MS susceptibility in Caucasian patients, whereas that the DQB1*06:02 allele confers genetic susceptibility regardless of ethnicity 8 .…”

Acute disseminated encephalomyelitis: clinical features, HLA DRB1*1501, HLA DRB1*1503, HLA DQA1*0102, HLA DQB1*0602, and HLA DPA1*0301 allelic association study

“…We found significantly association of HLA DQB1*0602, HLA DRB1*1501 and DRB1*1503 alleles with ADEM monophasic patients. The HLA DQB1*0602 allele confers genetic susceptibility to Brazilian MS patients from Rio de Janeiro City (RJC), independently of the genetic background [21][22][23] . The presence of a common allele conferring genetic susceptibility for both MS and ADEM in the same population was found by Idrissovaet al 20 among Russian MS and ADEM patients.…”

“…A linkage genetic study in children showed that ADEM was associated with HLA DRB1*01 and DRB1*017(03) in the Russian population, and these alleles are associated with MS in Russian patients 20 . In Brazil, MS has been associated with HLA DR2 in Caucasian 21 patients and with HLA DQB1*0602 independently of DRB1*1501, in African-descendent patients of Rio de Janeiro City (RJC) [21][22][23] .…”