With regard to the differences in the clinical characteristics between GADA-RIA and GADA-ELISA, in patients with GADA-RIA and GADA-ELISA (group C), the age of diabetes onset was younger, the titer of GADA-RIA was higher, and insulin deficiency and insulin use were higher compared with those without GADA-RIA and GADA-ELISA (group A) and those with GADA-RIA and without GADA-ELISA (group B). This evidence concerns the gene INS and diabetes mellitus.