Conditions such as obesity, insulin resistance and diabetes type 2, metabolic syndrome and familial combined hyperlipidemia (FCH) are associated with a decreased absorption of PS, probably for the increased expression of the ABCB4 (MDR2) transporter gene involved in the biliary excretion of sterols, while the pharmacological treatment with statins induces a compensatory increase in cholesterol absorption but also PS levels as well [114]. The gene discussed is ABCB4; the disease is obesity due to melanocortin 4 receptor deficiency.