The expression of methylation sensitive genes, such as ITGAL (CD11a), TNFSF7 (CD70), PRF1 (perforin) and CD40LG (CD40L), is increased in T cells from SLE patients, similar to normal T cells treated with DNA methylation inhibitors such as 5-azacytidine [3], [4], [5], [6]. The gene discussed is PRF1; the disease is systemic lupus erythematosus.