Biochemical Genetics: Introduction
Biochemical genetics examines the relationship between nucleotide sequence variation and physiological differences among members of the same or different species. If these differences are adaptive, the findings are central to a complete understanding of the ecological and evolutionary significance of the genetic variation. Historically, two approaches have been taken. In the first, genetic variation at a locus is initially detected, often as allozymes or null mutants, and the effect of this variation on the properties of the protein product and/or the fitness of the individuals with the different genotypes is assessed. In other words, the investigator attempts to demonstrate that the genetic variants have meaningful physiological effects. The second approach begins with the detection of adaptively important phenotypic differences, and proceeds toward an analysis of the underlying, often cryptic, genetic variation.