In this regard, inheritance of less inhibitory KIR-HLA genotypes and a higher number of activating KIR genes has been associated with the development of several autoimmune diseases such as ankylosing spondylitis, type 1 diabetes (T1D), multiple sclerosis, and rheumatoid arthritis [13, 15–17]. Here, KIR3DL1 is linked to type 1 diabetes mellitus.