Is microsomal triglyceride transfer protein (MTP) absent in individuals with abetalipoproteinemia compared to controls?
The absence of MTP in abetalipoproteinemic subjects suggests that a defect in MTP is the molecular basis for the disease and is required for lipoprotein assembly.
Abetalipoproteinemia is a human genetic disease that is characterized by a defect in the assembly or secretion of plasma very low density lipoproteins and chylomicrons. The microsomal triglyceride transfer protein (MTP), which is located in the lumen of microsomes isolated from the liver and intestine, has been proposed to function in lipoprotein assembly. MTP activity and the 88-kilodalton component of MTP were present in intestinal biopsy samples from eight control individuals but were absent in four abetalipoproteinemic subjects. This finding suggests that a defect in MTP is the basis for abetalipoproteinemia and that MTP is indeed required for lipoprotein assembly.
Wetterau et al. (Fri,) studied this question.