Other biochemical markers such as C-reactive protein (CRP) [8], the enzymes used as liver function tests (gammaglutamyl transferase, GGT [9-11], alanine aminotransferase, ALT; and aspartate aminotransferase, AST), butyrylycholinesterase (BCHE) [12,13]), serum ferritin [14] and uric acid [15,16] have also been shown to be associated with the risk of cardiovascular disease, hypertension, obesity, insulin resistance or metabolic syndrome. The gene discussed is GPT; the disease is obesity due to melanocortin 4 receptor deficiency.