sodium-dodecyl-sulfate and Hypobetalipoproteinemias

Familial hypobetalipoproteinemia is an autosomal codominant trait that can be caused by mutations in the apo B gene. Here we report a novel apo B gene mutation causing hypobetalipoproteinemia, that is associated with the synthesis of a truncated apo B protein in a young healthy male subject and his mother. The mutation is an A deletion at position 6627 of the apo B cDNA leading to a truncated protein of 2166 amino acids (apo B-48.4). This truncated apo B was detected mainly in VLDL, LDL and in trace amounts in HDL, but not in the lipoprotein deficient plasma fraction. Affected family members present with elevated levels of HDL-cholesterol, mainly due to an increase in HDL2 particles. Postprandial triglycerides and retinyl esters in the d < 1.006 g/ml lipoprotein in the proband showed a normal response to an oral fat load compared to a group of eight matched healthy controls. In summary this novel mutation is associated with hypobetalipoproteinemia with a normal fat absorption as expected for a protein with a length similar to that of apo B-48.

Topics: Adult; Aged; Apolipoprotein A-I; Apolipoprotein A-II; Apolipoprotein B-48; Apolipoprotein C-II; Apolipoprotein C-III; Apolipoproteins B; Apolipoproteins C; Apolipoproteins E; Base Sequence; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Cholesterol, VLDL; DNA Mutational Analysis; DNA, Complementary; Electrophoresis, Polyacrylamide Gel; Family Health; Female; Gene Deletion; Humans; Hypobetalipoproteinemias; Immunochemistry; Male; Middle Aged; Mothers; Oligopeptides; Pedigree; Phenotype; Point Mutation; Sodium Dodecyl Sulfate; Triglycerides