Abca1 deficient mice as a model for Tangier disease were generated by partial (111) or complete (112) replacement of the exons encoding the first ATP-binding cassette of Abca1. When fed on a high fat diet, Abca1 deficient mice were characterized by significantly decreased plasma HDL levels and lipid accumulation in several tissues including the kidney. The gene discussed is ABCA1; the disease is Tangier disease.