Nonetheless, as discussed in Nielsen GL et al., type 1 diabetes is a lifelong disease that is fatal without insulin treatment [16], and thus most individuals that suffered from type 1 diabetes between 1980 and 1987 were most likely admitted to a hospital at some point after January 1987, and hence classified as having type 1 diabetes, unless death occurred prior to January 1987. This evidence concerns the gene INS and type 1 diabetes mellitus.