Two single-nucleotide polymorphisms (SNP) were associated with RA: TIMP1 that was associated with RA in general (p = 0.035) and IL-9 receptor (IL9R) that was associated with anti-CCP-positive RA patients (p = 0.037) and with male RA patients (p = 0.010). Here, IL9R is linked to rheumatoid arthritis.