CD4 and systemic lupus erythematosus: For example, the SLE‐only locus does not interact with TNFAIP3 in stimulated CD4 T cells (Javierre et al, 2016) but has strong enhancer activity in transformed B cells (Whyte et al, 2013)—a cell type linked to SLE pathogenesis and enriched for SLE‐associated variants (Farh et al, 2015).