INS and metabolic syndrome: Genome-wide association studies (GWAS) and multiple candidate gene studies have reported that GCKR genetic variation is associated with metabolic parameters such as triglyceride (TG) levels [20–26], fasting blood sugar (FBS) [21–23, 26–28], and insulin [27, 28] or metabolic disorders like type 2 diabetes (T2DM) [27, 29], dyslipidemia (high triglyceride and low high-density lipoprotein cholesterol levels) [23, 30].