Sensitivity analyses supported the robustness of our findings.<h4>Conclusions</h4>There existed a genetically predicted potential association between the CD39+ CD8+ Tregs subset and the risk of DLBCL, while SLE and CD were genetically predicted to be potentially associated with the CD39+ CD8+ Tregs subset. This evidence concerns the gene ENTPD1 and systemic lupus erythematosus.