Principles of Genetics and Breeding

Preparation of metaphase chromosomes from fish tissues

The study of fish chromosomes has been in wide use in the recent past mainly to ascertain the taxonomic position of different species. The manipulation of chromosomes has proved a valuable technique and its application in fish breeding and culture is yet to be used extensively. The study of chromosomes is also helpful for genome manipulation and banding studies. The karyotype of a normal individuals usually consists of two sets (diploid) of chromosomes derived one set from each parent. In the case of diploid gynogens, the karyotype consists of duplicated set of chromosomes derived by the retention of second polar body while all the three sets of chromosomes, viz., the egg, the second polar body and the sperm together form the karyotype of a triploid individual.