Polyploidization in the fish family Cyprinidae, order Cypriniformes

In the fish family Cyprinidae, a diploid-tetraploid relationship exists among the various members examined as shown by chromosome analysis and measurements of the DNA content per cell. Duplications of individual gene loci in the tetraploids are demonstrated using the LDH- and 6-PGD-isoenzyme systems as gene markers, thus confirming the hypothesis of polyploidization. In some diploids endowed with an increased DNA content per cell, a duplication is demonstrable for the 6-PGD cistrons only, and not for the LDH cistrons, thus supporting the hypothesis that regionally confined duplications have occured independently of polyploidization.