Current research on enzyme polymorphism
Overall incidence of variation: Enzyme polymorphism is a well documented phenomenon in human populations. Estimates derived from electrophoretic studies indicate that approximately one third of all human enzymes exhibit genetic polymorphism where “polymorphism” is defined as the occurrence of heterozygotes with a frequency greater than 2%. Taken as a whole the data indicate that the average heterozygosity per locus is about 0.06 and this implies that any single individual in any human population is likely to be heterozygous at about 6% of the loci encoding enzyme proteins, for alleles which give rise to electrophoretically distinct isozyme forms (Harris & Hopkinson, 1976). The complexity of the isozyme patterns varies according to the subunit structure of the enzyme proteins and on average monomeric enzymes exhibit a higher incidence of genetic polymorphism than multimeric enzymes (Harris, Hopkinson & Edwards, 1977).
KeywordsEnzyme Protein Subunit Structure Human Enzyme Hypoxanthine Phosphoribosyl Transferase Enzyme Polymorphism
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