The genetic variants of OCTN1 rs1050152 and intron 1 rs3792876 mutation affecting the binding of runt-related transcription factor 1 protein (RUNX-1) for transcription of SLC22A4 are reported to have a strong association with diabetes mellitus, inflammatory bowel disease, rheumatoid arthritis and autoimmune thyroiditis suggesting the involvement of SLC22A4 in the autoimmune regulatory pathway [13–16]. The gene discussed is SLC22A4; the disease is rheumatoid arthritis.