Recently, several studies indicated that SNVs of PPARs, such as Leu(162)Val and Val(227)Ala of PPARα, +294T > C of PPARβ/δ, Pro(12)Ala, and C1431T of PPARγ, are significantly associated with the onset and progression of MetS and T2DM in different populations worldwide. The gene discussed is PPARA; the disease is type 2 diabetes mellitus.