Case–control association between children carrying one or two risk alleles and allele-negative mothers’ rheumatoid arthritis status
| Risk allele group | n Proportion of allele-negative mothers with allele-positive children | RA (mother) OR (95% CI)* | p Value | |
| Cases | Controls | |||
| HLA-DRB1 | ||||
| Shared epitope + | 11/31 | 148/605 | 1.7 (0.8 to 3.7) | 0.18 |
| DERAA + | 35/152 | 97/779 | 1.7 (1.0 to 2.7) | 0.03 |
| Valine + (AA position 11) | 16/63 | 114/714 | 1.7 (0.9 to 3.3) | 0.11 |
| Lysine + (AA position 71) | 26/58 | 127/583 | 2.7 (1.5 to 4.8) | 0.001 |
| Alanine + (AA position 74) | 6/8 | 100/151 | 1.4 (0.3 to 7.4) | 0.70 |
| HLA-B | ||||
| Aspartic acid + (AA position 9) | 17/122 | 85/768 | 1.2 (0.7 to 2.2) | 0.58 |
| HLA-DPB1 | ||||
| Phenylalanine + (AA position 9) | 8/10 | 49/61 | 0.4 (0.04 to 3.7) | 0.43 |
*95% CI for the association between having at least one child (born prior to diagnosis for cases) with one or two alleles (+) of each risk allele group compared with none and RA among mothers. Estimates adjusted for number of live births and mother’s carrier status at all other risk allele groups.
AA, amino acid; RA, rheumatoid arthritis.