The role of major genes in main productive and economical traits in goat

Till now a large number of major genes related to main productive and economical traits in goat have been identified. These genes have favorable effects on physiological rate، metabolism and expressing the emergence of phenotypes in terms of economical traits. Performance of these genes on main economical traits is different. Some of these genes have synergistic effects while others have antagonistic effects on the biological nature of the organism in terms of expression and emergence of phenotype of traits. Hence، breeders should be aware of actions and effects of these genes as choosing a type of particular trait can affect other traits too. Therefore، diagnosing the major genes and also the rate of mutation in them that cause changing in the expression of the gene and phenotype of economical traits، provides the possibility to search for some genetic markers related to such important economical traits for breeders. Hence، it can be used as subsidiary tool in selection of parental herd in low ages and also in direct surveying of the position of the quantitative trait and designing an eugenics program in the future. The basic and major genes in goats have a significant role in performance، metabolism، sex determination، reproduction and resistance against diseases. Therefore، the aim of this study is reviewing the major genes which are effective in productive traits such as growth traits، reproduction، milk and wool production and resistance against diseases in goat.