Genetic Recombination Between The Regulatory And The Stuctural Elements Of A Gene Coding For The Enzyme Phosphoglucomutase In Rainbow Trout (Salmo gairdneri)

Abstract

Rainbow trout doubly heterozygous for both the structural and the regulatory genes (100/90 ; a/b) of phosphoglucomutase (PGM) were crossed with doubly homozygous individuals (100/100 ; a/a) to produce the progeny used in the genetic testing. Allelic variants of both the regulatory and the structural elements (represented by allelic isozymes) were separated and identified using starch gel enzyme electrophoresis. The number of recombinant genotypes was then used as an estimate of the frequency of recombination between the structural and the regulatory elements of the pgm gene. Results show that such recombination is a rare event, supporting previous indications that the regulatory gene is cis acting and is also tightly linked to the structural gene.