CD4 and rheumatoid arthritis: In rheumatoid arthritis, MAGMA across five ancestry groups identified 34 novel loci, and multiancestry fine‐mapping identified a putative causal variant at the LEF1 locus, which is of interest as LEF1 has a role in CD4+ T cells, which are relevant to rheumatoid arthritis biology (Ishigaki et al., 2022).