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.
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: Stephen C Gale; Li Gao; Carmen Mikacenic; Susette M Coyle; Nicholas Rafaels; Tanda Murray Dudenkov; Jennifer H Madenspacher; David W Draper; William Ge; Jim J Aloor; Kathleen M Azzam; Lihua Lai; Perry J Blackshear; Steven E Calvano; Kathleen C Barnes; Stephen F Lowry; Siobhan Corbett; Mark M Wurfel; Michael B Fessler Journal: J Allergy Clin Immunol Date: 2014-03-18 Impact factor: 10.793
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Authors: Zaheda H Radwan; Xingbin Wang; Fahad Waqar; Dilek Pirim; Vipavee Niemsiri; John E Hokanson; Richard F Hamman; Clareann H Bunker; M Michael Barmada; F Yesim Demirci; M Ilyas Kamboh Journal: PLoS One Date: 2014-12-12 Impact factor: 3.240
Authors: Dilek Pirim; Zaheda H Radwan; Xingbin Wang; Vipavee Niemsiri; John E Hokanson; Richard F Hamman; Eleanor Feingold; Clareann H Bunker; F Yesim Demirci; M Ilyas Kamboh Journal: PLoS One Date: 2019-03-26 Impact factor: 3.240