allozymes

Allozymes are variant forms of an enzyme that are coded for by different alleles at the same gene locus. This means that within a population, there can be multiple versions of the same enzyme, each with a slightly different amino acid sequence. These differences in amino acid sequence can lead to variations in the enzyme's catalytic activity, substrate specificity, or electrophoretic mobility. Allozymes are a direct reflection of genetic variation within a population and are therefore useful markers in population genetics and evolutionary studies.

The study of allozymes, known as allozyme electrophoresis, became a foundational technique in molecular population genetics. By separating proteins based on their charge and size using gel electrophoresis, researchers could infer the genotypes of individuals at specific enzyme loci. Different allozymes migrate at different rates on the gel, creating distinct banding patterns. These patterns allow scientists to estimate allele frequencies and genetic diversity within and between populations, track gene flow, and understand population structure. While newer molecular techniques like DNA sequencing have largely superseded allozyme analysis, allozymes remain a valuable tool for certain research questions, especially in ecological and conservation genetics where cost-effectiveness and ease of implementation are important. They provide a snapshot of genetic variation at the protein level, reflecting functional differences in enzymes crucial for cellular processes.