The IVW estimates replicated the TSMR results on the causal effects of geneticallypredicted β2M on B-cell malignancies, confirming that β2M was associated with increasedrisk of DLBCL (OR: 2.098; 95% CI: 1.358-3.242; P = 8.28 ×10−4; FDR = 4.14 × 10−3) and HL (OR: 1.581; 95% CI: 1.167-2.142; P = 3.13 × 10−3; FDR = 5.22 × 10−3) but was not associated with CLL (OR: 0.870; 95% CI: 0.608-1.246; P = 0.448; FDR = 0.448) or MM (OR: 1.189; 95% CI: 0.943-1.498; P = 0.144; FDR = 0.180). This evidence concerns the gene B2M and diffuse large B-cell lymphoma.