title: The apolipoprotein E polymorphism: a comparison of allele frequencies and effects in nine populations.
abstract: Application of uniform methods for measuring the apolipoprotein (apo) E polymorphism and plasma cholesterol levels in nine populations (Tyrolean, Sudanese, Indian, Chinese, Japanese, Hungarian, Icelandic, Finnish, and Malay) revealed significant heterogeneity among them in apo E type frequencies and mean cholesterol levels. The major apo E types in all populations were E3/2 (frequency range from 7.0% in Indians to 16.9% in Malays), E3/3 (frequency range from 39.8% in Sudanese to 72.1% in Japanese), and E3/4 (frequency range from 11.3% in Japanese to 35.9% in Sudanese). Mean cholesterol levels ranged from 144.2 mg/dl in the Sudanese to 228.5 mg/dl in the Icelandics. Two-way analysis of variance of the effect of population and apo E type on cholesterol levels showed no significantly interaction effect, indicating that the effects of apo E type on cholesterol levels do not differ significantly among the populations. The overall average excess for the epsilon 2 allele was -14.12 mg/dl (range -31.63 to -8.82 mg/dl); for the epsilon 3 allele, 0.04 mg/dl (range -1.87 to 1.58 mg/dl; and for the epsilon 4 allele, 8.14 mg/dl (range -1.71 to 13.31 mg/dl). Despite the apparent heterogeneity in these values, especially for the epsilon 4 allele, comparison of the average excesses by a method of repeated sampling with random permutations revealed no significant difference in effects among populations. These data indicate that a given apo E allele acts in a relatively uniform manner in different populations despite differences in genetic background and environmental factors.
authors.affiliation: Center for Demographic and Population Genetics, University of Texas Health Science Center, Houston 77225.
authors.forename: D M
authors.initials: DM
authors.lastname: Hallman
authors.forename: E
authors.initials: E
authors.lastname: Boerwinkle
authors.forename: N
authors.initials: N
authors.lastname: Saha
authors.forename: C
authors.initials: C
authors.lastname: Sandholzer
authors.forename: H J
authors.initials: HJ
authors.lastname: Menzel
authors.forename: A
authors.initials: A
authors.lastname: Csázár
authors.forename: G
authors.initials: G
authors.lastname: Utermann
mesh_terms: D000483:Alleles; D001057:Apolipoproteins E / Q000097:blood / Q000235:genetics* / Q000302:isolation & purification; D005006:Ethnicity; D005787:Gene Frequency; D006801:Humans; D007525:Isoelectric Focusing; D010641:Phenotype; D011110:Polymorphism, Genetic
chemical_list: D001057:Apolipoproteins E