Table 3

Comparison of PTPN22 1858 genotypes in rheumatoid arthritis patients stratified according to anti-cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor with all controls


CT + TT genotype, n (%)
CC genotype, n (%)
Minor allele frequency
Cases versus all controlsa









χ2
P value
Pc value
Odds ratio
95% confidence interval

Anti-CCP antibody-positive
113 (35.5)
205 (64.5)
0.196
24.99
0.0000006
0.0000024
2.01
1.51–2.67
Anti-CCP antibody-negative
40 (26.7)
110 (73.3)
0.145
1.97
0.16046
0.64184
1.32
0.88–2.00
Rheumatoid factor-positive
96 (36.4)
168 (63.6)
0.199
24.49
0.0000007
0.0000028
2.08
1.53–2.82
Rheumatoid factor-negative
28 (27.5)
74 (72.5)
0.142
1.87
0.17164
0.68656
1.38
0.85–2.23

Pc, corrected P value. aControls presented in Table 2

Kokkonen et al. Arthritis Research & Therapy 2007 9:R56   doi:10.1186/ar2214