Broad Spectrum Utilities of Microsatellite in Fish and Fisheries

Microsatellites are short segments of repetitive DNA sequences distributed throughout the eukaryotic genome and used as molecular markers for various purposes in applied biology. These are tandem repeats of 1-6 nucleotides like di-, tri-, tetra- or hexa nucleotides occurring at high frequency in the nuclear genomes of different taxa including most of the vertebrates. These constitute only a few percent of the genomes depending on their compactness but have become the markers of choice for high-resolution population analysis due to high variability, ease and accuracy of assaying. In modern trends of genetics, molecular biology, biotechnology and genetic engineering pertinent to animal, plant and microbes, these markers have contributed a lot to upgrade the knowledge and information. These are preferred as extremely valuable tools for genome mapping in many organisms over erstwhile markers and are integrated with other morphological features of various organisms helping to identify species or strains accurately. These have been used extensively since last few decades for versatile purposes in various parts of world and are applied to different organisms where fishes are not an exception. As versatile genetic markers, these have been applied in many studies on genetics and resource management of fishes as well as for analyzing pedigree, population structure, genome variation, evolutionary process and fingerprinting. This strengthens management and protection of fish germplasm. These are also integrated with many other tools of recent advancement in biotechnology, molecular biology and genetic engineering vis-a-vis other traditional technologies like captive breeding and fish milt cryopreservation for conserving genetic diversity and rehabilitation of the natural populations of fishes. However, there is still a long way to go before these are applied in each species of fish. The present article reviews a compilation of many references on utilities of microsatellite markers for different purposes applied to various types of fishes and non fishes.