Development of molecular biology during the past three decades has created new oppurtunities for the selection and genetic improvement of livestock. DNA markers have already provided wide applications in parentage verification, individual identification and control of genetic disorders. The ultimate use of DNA markers would be to identify quantitative trait loci in order to practice genotypic selection. It is possible that application of molecular markers in animal breeding and genetics can be studied under two main headings as shortrange or immediate and longrange. Shortrange or immediate applications are individual identification, parentage determination, control of genetic disorders, genetic distance estimation, determination of twin zygosity and sexing of preimplantation embryos. Long range applications are genome mapping, determination of quantitative trait loci, marker assisted selection and biodiversity and conservation of genetic resources studies.