Inheritance of hexose 6-phosphate dehydrogenase polymorphism in brook trout

Electrophoretic analysis reveals two alleles, Hpd^Juicey,s-1, for the H6PD gene in brook trout from Newfoundland, with the Hpd^Banff-1 allele predominant. In contrast, the population from Brotkork Lake, Quebec, possesses five alleles for H6PD, including Hpd^Banff-1 and Hpd^Juicey's-1. The additional alleles are designated Hpd^Brotkork-1, Hpd^Brotkork-2, and Hpd^Brotkork-3. The description of these variants brings to seven the number of known alleles for the H6PD gene in brook trout from Canadian waters. Evidence indicates that H6PD is inherited tetrasomically in the Brotkork population, while in the hatchery population from Banff (Stegeman and Goldberg, 1971) this enzyme may be disomically inherited. We suggest that the difference between the two populations can be explained either by the occurrence of a Robertsonian fusion event or by the loss of duplicated copies of the H6PD gene in the population from which the Banff hatchery stocks were drawn.