Few candidate gene studies reported associations of single nucleotide polymorphisms (SNPs) in CLOCK, ARNTL (encoding BMAL1), and PER2 with risk factors for the metabolic syndrome and type-2 diabetes, such as abdominal obesity, hypertension, fatty liver, and an atherogenic lipid profile [16–22]. This evidence concerns the gene BMAL1 and type 2 diabetes mellitus.