The ATP-binding cassette transporter subfamily A member 1 (ABC-A1) and type 2 diabetes: an association beyond HDL cholesterol.

Recent findings from several groups demonstrate that ABC-A1 participates in the pathogenesis of the metabolic syndrome and type 2 diabetes. A variant of the ABC-A1 gene (R230C) is associated with the metabolic syndrome and its co-morbidities in Mexicans. Its presence is associated with an increased risk for obesity, the metabolic syndrome and type 2 diabetes. R230C is found exclusively in Amerindian and Amerindian-derived populations. Moreover, animal models confirm the participation of ABC-A1 in the pathogenesis of diabetes. Mice lacking AbcA1 specifically in beta cells had glucose intolerance at 8 weeks of age. The absence of ABC-A1 led to cholesterol accumulation within the beta cell plasma membrane, suggesting that cholesterol may play a role in the insulin secretory pathway. In conclusion, ABC-A1 may be more than a determinant of HDL-cholesterol. It may provide a link between components of the metabolic syndrome and atherosclerosis.