title: Integrated role of two apoliprotein E polymorphisms on apolipoprotein B levels and coronary artery disease in a biethnic population.
abstract: BACKGROUND
  Apolipoprotein E (ApoE) plays a major role in lipoprotein metabolism and genetic variability of ApoE confers susceptibility to coronary artery disease (CAD). Beyond variability in the coding region, promoter polymorphisms in the ApoE gene impact on ApoE transcription.
  
  
  METHODS
  We determined the ApoE - 491 A/T promoter polymorphism, ApoE isoforms, lipid and lipoprotein levels, and CAD risk factors in 313 Caucasians and 215 African Americans.
  
  
  RESULTS
  Caucasians had a lower ApoE T allele frequency compared to African Americans (18.1% vs. 32.3%, P < 0.05). Among T/* carriers, ApoB levels were significantly lower in Caucasians, but significantly higher among African Americans, in both cases compared to A/A homozygotes (P = 0.017, and P = 0.012). For a given -491A/T genotype, levels of atherogenic lipoproteins differed across ApoE2/E3/E4 isoforms among African Americans, but not Caucasians, as T/* carriers with ApoE4 had significantly higher ApoB levels compared to T/* carriers with ApoE2 (P = 0.010). Among patients with CAD, Caucasian A/A homozygotes and African American T/* carriers had higher ApoB levels compared to the same genotype without CAD (P = 0.007, P = 0.049, respectively).
  
  
  CONCLUSIONS
  We observed an ethnicity-specific variability in ApoB levels across the ApoE - 491 A/T polymorphism and a modulatory impact on this pattern by ApoE2/E3/E4 isoforms.
authors: Department of Medicine, University of California, Davis, California, USA.
authors: Zeynep
authors: Z
authors: Ozturk
authors: Byambaa
authors: B
authors: Enkhmaa
authors: Neil S
authors: NS
authors: Shachter
authors: Lars
authors: L
authors: Berglund
authors: Erdembileg
authors: E
authors: Anuurad
mesh_terms: D000328:Adult; D000368:Aged; D001055:Apolipoproteins B / Q000097:blood*; D001057:Apolipoproteins E / Q000235:genetics* / Q000502:physiology; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000097:blood* / Q000208:ethnology* / Q000235:genetics*; D004843:Epistasis, Genetic / Q000502:physiology; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000502:physiology; D011153:Population; D020033:Protein Isoforms / Q000235:genetics
chemical_list: D001055:Apolipoproteins B; D001057:Apolipoproteins E; D020033:Protein Isoforms