OGA and type 2 diabetes mellitus: Interestingly, single nucleotide polymorphisms (SNPs) on OGA (also called MGEA5 for meningioma expressed antigen 5) gene and GFPT2 (for GFAT isomerizing 2) gene, coding the glutamine fructose-6-phosphate amidotransferase (GFAT) rate-limiting enzyme controlling the production of UDP-GlcNAc, are associated with increased T2D risk in American-Mexican and Caucasian populations, respectively (56, 57).