CYP8B1 was one of the key enzymes of bile acids synthesis, and ablating CYP8B1 in mice led to reduced absorption of dietary triglyceride with intact triglyceride hydrolysis and improved insulin sensitivity, suggesting CYP8B1 as a potential therapeutic target for obesity and diabetes [27]. The gene discussed is CYP8B1; the disease is obesity due to melanocortin 4 receptor deficiency.