We identified a significant association of RTKN2 (rs3125734) with GD (P = 3.4×10−5, OR = 1.24, 95% CI = 1.12–1.37), whereas no significant associations were detected in NFKBIE (rs2233434) with either disease or in RTKN2 (rs3125734) with SLE (Table S3). Here, RTKN2 is linked to systemic lupus erythematosus.