A disorder of lipid metabolism inherited as an autosomal recessive trait characterized by the near absence of APOLIPOPROTEINS B and apoB-containing lipoproteins in plasma. Microsomal triglyceride transfer protein is deficient or absent in enterocytes. Clinical and laboratory findings include acanthocytosis, hypocholesterolemia, peripheral neuropathy, posterior column degeneration, ataxia, and steatorrhea. Intellectual abilities may also be impaired. (Menkes, Textbook of Child Neurology, 5th ed, p118; Curr Opin Lipidol 1994 Apr;5(2):81-6)