In the report by Okada et al. (11), the tissue distribution of AFF1 has also been investigated, andtheir results revealed that AFF1 transcripts were prominentlyexpressed in CD4+ and CD19+ peripheral blood lymphocytes.Taken together, these observations indicate that AFF1 is implicatedin the development of lymphocytes, and its altered expression, caused by allelesubstitution, might contribute to the development of autoimmune diseases (26). This evidence concerns the gene CD4 and autoimmune disease.