DDAH1 and type 2 diabetes mellitus: We aimed to determine whether serum ADMA levels are influenced by common single nucleotide polymorphisms (SNPs) in DDAH1 and DDAH2 genes in a large Australian cohort of individuals with type 2 diabetes, and found that genetic variation in the DDAH1 and DDAH2 genes significantly and additively affects serum ADMA concentrations.