IFIH1 and type 1 diabetes mellitus: Missense single-nucleotide polymorphisms (SNPs) resulting in the MDA5 variants E627* (rs35744605), R843H (rs3747517), I923V (rs35667974), and T946A (rs1990760) are associated with protection from T1D.37–43 The E627* and I923V variants are rare, while R843H and T946A are common.