TGFB1 and type 2 diabetes mellitus: This study aimed to determine the genotypic and allelic frequencies of the <i>TGF-β1</i> gene (rs1800469 and rs1800470) as well as to test whether there is an association between <i>TGF-β1</i> single-nucleotide polymorphisms (SNPs) and DN development in Saudi patients with T2D.<h4>Methods</h4>This case-control study involved 204 samples, including 76 controls, 81 patients with T2D without DN, and 47 patients with T2D with DN.