Table 4.

Shared epitope and DRB1*0901 in anti-CCP-positive and anti-CCP-negative unaffected family members. Unaffected family members included are first-degree relatives (n = 132) or more distant relatives (n = 34) who had HLA typing and anti-CCP antibody assay results. Odds ratios for risk of positive anti-CCP antibodies due to SE and DRB1*0901 were calculated by comparison of anti-CCP antibody-negative and anti-CCP-positive unaffected relatives.

HLA-DRB1
Genotype
Anti-CCP-negative (n = 139) NANTI-CCP-positive (n = 27) NOR (95% CI)p
Any SE106221.37 (0.48, 3.90)0.554
SE/X72151.38 (0.46, 4.10)0.567
SE/SE3471.36 (0.39, 4.71)0.628
*0901643.86 (1.01, 14.73)0.059
SE/*0901544.66 (1.16, 18.66)0.04