Molecular Markers and its applications in livestock

Molecular markers are the positions on genome where certain alterations in DNA sequences present among members of the same species which reveals polymorphism at the DNA level. A molecular marker shows an alteration in expression of mRNA leads to abnormal protein function that correlates with the certain phenotypic or genetic abnormality in animals or cause progression of a disease, with the susceptibility of the disease. The most broadly used of molecular markers in livestock genomic research include Restriction Fragment Length Polymorphism (RFLP) that recognize and cut DNA at specific alteration sites, Random Amplified Polymorphic DNA (RAPD) may used in analysis of mixed genome samples and for development of target specific probes, microsatellite markers that help in scoring of alleles and single Nucleotide Polymorphism (SNP) markers that recognizes single base modification in DNA sequences. Genetic improvement or genetic selection of livestock has been mainly dependent on the selective breeding with superior phenotypes. The uses of molecular genetics techniques in with association of usual animal breeding tools are important to equilibrate the process of selection to optimize the animal breeding program. In this regard, the use of molecular markers is significantly crucial and it certainly has added advantages over conventional breeding techniques. The present review deals with molecular markers and their application in livestock research leads to the association of molecular markers with certain livestock trait viz. milk production, growth, reproduction, and genetic diseases assist researcher and breeders for production of elite livestock.