Markers in RAD54B (rs3019279), AID (rs2580874 and rs714629) showed significant association with the combined IgAD/CVID cohort, and SNPs in MSH2 (rs3771276 and rs6729015), RAD50 (rs2237060), and RAD52 (rs10849605) were associated with IgAD. The gene discussed is MSH2; the disease is common variable immunodeficiency.