Apolipoprotein polymorphisms and phenotypic variability in American Samoans: Preliminary data

Human apolipoprotein genetic variation is associated with phenotypic variability in body habitus and in lipid and glucose metabolism, interrelated aspects of human physiology. In this study, structural variation at the apolipoprotein E and H loci, documented for 67 residents of American Samoa, was investigated for associations with body habitus, plasma glucose, glycated hemoglobin, pulse rate, and blood pressure. Compared to men with the common APO E*3 allele, those with APO E*2 had higher weight, percent trunk fat, ratio of subscapular to triceps skinfold, and larger subscapular, suprailiac, and medial calf skinfolds; men with the APO E*4 allele had lower weight, body mass index (BMI), upper arm circumference, estimated arm muscle circumference, and a smaller suprailiac skinfold. Such variability by apolipoprotein E types was not observed in Samoan women nor when men and women were combined for analysis with or without statistical control for sex. At the APO H locus, little difference in aspects of body habitus was observed between men carrying the most common APO H*2 allele and the less common APO H*1 allele. Percent trunk fat and the subscapular to triceps skinfold ratio tended to be larger in women with the APO H*1 allele. Plasma glucose and glycated hemoglobin were lower in Samoans with the APO E*2 and E*4 alleles, but higher in those with the APO H*1 allele. Blood pressure and pulse rate were lower and higher, respectively, in those with the APO E*4 allele. The observed associations differ from those observed in Caucasian, Japanese, and Hispanic samples, and support suggestions that associations between apolipoprotein polymorphisms and morphological measures vary across ethnic groups. © 1993 Wiley-Liss, Inc.