GLIS3 and type 2 diabetes mellitus: Thirteen circRNAs co-localised with the genomic regions encompassing the GWAS association signals for T2D; 2 circRNAs from the CTBP1 gene (in rs6819243 region), one circRNA from the GLIS3 gene (rs10758593), one circRNA from the HMG20A gene (rs7177055), two circRNAs from the IDE gene (rs1111875), two circRNAs from the SPPL3 gene (rs12427353) and five circRNAs deriving from the THADA gene (rs10203174).