Human apolipoprotein A-IV polymorphism: frequency and effect on lipid and lipoprotein levels.
Human apolipoprotein (apo) A-IV is genetically polymorphic, the apo A-IV polymorphism being controlled by two common alleles, A-IV1 and A-IV2. We have developed a method for typing the apo A-IV polymorphism by Western blotting using polyclonal rabbit antiapo A-IV as the first and gold-labeled antirabbit IgG as the second antibody. Apolipoprotein phenotypes were determined in plasma samples from 473 tiroleans. The frequencies of the apo A-IV alleles in this sample were f(A-IV1) = 0.919, f(A-IV2) = 0.077, and f(A-IV3) = 0.004. Although average triglyceride levels were lower in apo A-IV 2-1 heterozygotes, average total serum cholesterol and triglyceride levels were not significantly different among apo A-IV types. High density lipoprotein (HDL) cholesterol was significantly increased in individuals with the A-IV 2-1 phenotype. We estimate that genetic variation at the apo A-IV gene locus accounts for 11% of the total variability in HDL-cholesterol levels in Tiroleans. The effects of the apo A-IV polymorphism described here are consistant with, and may serve to enrich, our limited knowledge of the role of apo A-IV in lipid metabolism.
Menzel
H J
HJ
Institut für Medizinische Biologie und Genetik der Universität, Innsbruck, Austria.
Boerwinkle
E
E
Schrangl-Will
S
S
Utermann
G
G
D001054:Apolipoproteins A / Q000235:genetics*; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D005787:Gene Frequency; D006801:Humans; D007526:Isoelectric Point; D010641:Phenotype; D011110:Polymorphism, Genetic; D014280:Triglycerides / Q000097:blood
D001054:Apolipoproteins A; D008076:Cholesterol, HDL; D014280:Triglycerides; C022205:apolipoprotein A-IV; D002784:Cholesterol