PRTN3 and rheumatoid arthritis: No significant associations were observed when stratified for ACPA status alone (Table 2), but interestingly, the MBL-high genotype tended to be associated with the RF-negative/ACPA-positive subgroup of RA (OR 1.54, 95% CI 0.99 to 2.38) rather than the RF-negative/ACPA-negative subgroup (OR 1.14, 95% CI 0.89 to 1.47).