Principles of Genetics and Breeding

11.1.1 Genetics of qualitative and quantitative phenotypes

The mechanism of inheritance in fishes is known primarily on intensive studies of very few members of a single order, the Cyprinodontiformes – particularly the guppy (Lebistes reticulates), platyfishes and sword tails (Xiphophorus), and the medaka or Asiatic rice fish (Oryzias latipes).

In recent years, knowledge of the field has been enlarged through researches on carp and goldfish (Cyprinidae), Anatolian cyprinodontids, experiments with trouts and chars (Salmoninae), and on scattered representatives from a few other groups.

Although much is known of the genetics of the goldfish (Carassius auratus), the documentation is chiefly in Japanese. There remains the vast majority of fishes including the primitive, jawless vertebrates (Cyclostomata), for which almost no genetic information is available.

There are two main groups of trait – qualitative and quantitative.