Fasting glucose was associated with a known biomarker of obesity, namely cysteine-s-sulphate, which is involved in intracellular insulin action13 and n-acetylgarginine, which has been suggested to modulate glucose homeostasis, insulin sensitivity and promote lipolysis, through arginine-nitric oxide modulation of intracellular AMPK and PI3K14. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.