Therefore, the aim of the present study was to analyze the distribution of HLA-B alleles in TA (n = 40) and Tb (n = 34) patients and healthy controls (72 exposed and 99 nonexposed).
The genetic susceptibility with HLA-B*52, as well as additional classical alleles and loci, implicate both HLA class I and class II involvement in TAK.
In spite of the loose clinical relationship between TA and Tb, we did not detected any genetic relationship between them when the HLA-B alleles were analyzed in these groups of patients.
Combined analyses of polymorphisms in the HLA-B and MICA genes with those in the microsatellites suggest that there are two different disease-susceptible loci for Takayasu's arteritis; one is mapped near the C1-2-A locus and the other is more closely linked to the HLA-B gene than to the MICA gene, because there are at least two different disease-associated HLA-B haplotypes, HLA-B*52 and -B*39.2 haplotypes, in which the disease-associated C1-2-A allele is shared in common.
Because two HLA-B alleles, HLA-B51 and B39.1, which are similar but different at the epitope from HLA-B52 and B39.2, respectively, are not associated with Takayasu arteritis, 63Glu and 67Ser are supposed to be involved in the pathogenesis.
Identification of Susceptibility Loci in IL6, RPS9/LILRB3, and an Intergenic Locus on Chromosome 21q22 in Takayasu Arteritis in a Genome-Wide Association Study.
The association of Takayasu arteritis with Amerindian and Asian HLA-DRB1 alleles (DRB1*1602 and DRB1*1001) in the Colombian mestizo patients reported here, and with HLA-B*3906 previously reported in Mexicans, suggest the possibility that some HLA and disease associations are markers for ethnicity of a population carrying a disease gene which is present in an admixed population with the disease.
Interestingly, HLA-B*39061 and B-39062 share the 3' end of intron 2 and the 5' end of exon 3 with HLA-B*5101 and B*52012, alleles associated to Takayasu arteritis in Japanese.
A novel susceptibility locus in the IL12B region is associated with the pathophysiology of Takayasu arteritis through IL-12p40 and IL-12p70 production.
Four single nucleotide polymorphisms (SNPs) those locate in the IL12B region (rs56167332), the MLX region (rs665268), the FCGR2A/FCGR3A locus (rs10919543), and the HLA-B/MICA locus (rs12524487), associated with TA in different population, were genotyped in 123 Chinese TA patients and 147 healthy controls from January 2013 to August 2014.
Outside the HLA region, only one polymorphism located nearby the IL12B gene surpassed the study-wide significance threshold in the meta-analysis of the discovery datasets (rs755374, P = 7.54E-07; OR<sub>GCA</sub> = 1.19, OR<sub>TAK</sub> = 1.50).
The frequencies of IL12B 1188 C allele (p = 0.03, OR = 1.7) and CC genotype (p = 0.007, OR = 3.7) were both higher in TA patients than in control subjects.
We demonstrated a allele association between the four SNPs of IL12B and TA (rs6871626: OR 1.52, 95% CI 1.26-1.83; rs4921492: OR 1.46, 95% CI 1.21-1.75; rs60689680: OR 1.41, 95% CI 1.17-1.69; rs4921493: OR 1.45, 95% CI 1.21-1.75, all P <sub>c</sub> < 10<sup>- 3</sup> ).
Four single nucleotide polymorphisms (SNPs) those locate in the IL12B region (rs56167332), the MLX region (rs665268), the FCGR2A/FCGR3A locus (rs10919543), and the HLA-B/MICA locus (rs12524487), associated with TA in different population, were genotyped in 123 Chinese TA patients and 147 healthy controls from January 2013 to August 2014.