PDE2A and rheumatoid arthritis: Additionally, SNP rs3781913(A) located within the PDE2A gene on chromosome 11 was also found to be associated with RA [OR = 0.32 (CI 0.12 – 0.83); p = 0.020] and CD [OR = 0.46 (CI 0.24 – 0.91); p = 0.024] in the same direction.