Among them, 18 KOs are significantly enriched in the obesity group, including digestive enzyme-coding genes like beta-galactosidase (K01190), fucosidase (K15923, K01206), glucosidase (K01187, K05349), and starch utilization system proteins (K21571, K21573, K21572). The gene discussed is GLB1; the disease is obesity due to melanocortin 4 receptor deficiency.