The titres of the anti-CD300e antibody was 0.1000 (0.0515–0.2050) [median (range), arbitrary unit] in FT1D patients (acute phase, n = 26), 0.0784 (0.0583–0.1515) in FT1D patients (sub-acute phase, n = 26), 0.0828 (0.0624–0.1356) in FT1D patients (chronic phase, n = 13), 0.0721 (0.0534–0.1201) in T1AD patients, 0.0675 (0.0551–0.1056) in T2D patients, 0.0672 (0.0539–0.1007) in AITD patients and 0.0636 (0.0524–0.0877) in HC. This evidence concerns the gene CD300E and type 2 diabetes mellitus.