Skip to main content

Table 3 Overall effect estimation of genotypes resulting from the classification of HLA-DRB1 alleles on rheumatoid arthritis susceptibility

From: New classification of HLA-DRB1alleles in rheumatoid arthritis susceptibility: a combined analysis of worldwide samples

Genotypes Genotype distribution, n (%) OR (95% CI) P values
  RA cases, n = 758 Controls, n = 789   
S2/S3P 39 (5.1%) 7 (0.9%) 7.25 (3.26–16.14) <10-5
S3P/S3P 74 (9.8%) 31 (4%) 5.15 (2.91–9.12) <10-5
S2/S2 24 (3.2%) 8 (1%) 4.95 (2.2–11.18) <10-4
S2/L 121 (16%) 78 (9.9%) 2.41 (1.60–3.65) <10-4
S3P/L 179 (23.6%) 136 (17.2%) 2.33 (1.57–3.45) <10-4
L/L 321 (42.3%) 529 (67%) 1  
  1. S1, S2, S3P, S3D, and X allele groups were defined according to the amino acid sequence at positions 70 to 74. According to the approach proposed by Michou and colleagues [9], we pooled the three low-risk allele groups (S1, S3D, and X), so called L alleles. Thus, in subsequent analyses, we considered only three allele groups (S2, S3P, and L alleles), with six corresponding genotypes [12]. The reference genotype is L/L. The combined odds ratios (ORs) and 95% confidence intervals (CIs) evaluate the significance of the global effect of the different HLA-DRB1 genotype groups on rheumatoid arthritis (RA) susceptibility over all population samples. P values were calculated with the Mantel-Haenszel method.