Variability of polymorphic cellular enzymes in medical students with different serum lipid levels: a preliminary...

Groups of male Caucasian medical students who had, relative to their classmates, eitherhigh or low lipid levels were screened for electrophoretic variants of haptoglobin, transferrin, and 10 polymorphic erythrocyte enzymes. Members of both the "high" and "low" lipid groups were found to be polymorphic at 7 genetic loci, 6 of which were enzymatic. Consistently, at most polymorphic loci the high lipid groups had somewhat higher frequencies of nonpredominant phenotypes (patterns other than the phenotype reported to occur most frequently in U.S.A. Caucasian populations). A higher frequency of the less common nonpredominant phenotypes (reported Caucasian population frequency less than 0.200) in the high lipid groups was primarily responsible for the observed variations in the phenotypic distributions. Gene frequency distributions were correspondingly skewed. In 14 comparisons between the high and low lipid groups the least common allele of the 7 polymorphic series had a higher frequency in the high lipid group 9 times and in the low lipid group only once. Collectively, our preliminary observations suggest quantitative and qualitative genetic trends related to serum lipid levels that warrant more extensive investigation.