BACKGROUNDEndometriosis is a common benign disease whose etiology is still unknown. However, there is increasing evidence that genetic susceptibility is a risk factor for the development of the disease. It is generally accepted that endometriosis is inherited as a complex genetic trait, in which multiple gene loci interact with each other and the environment to produce the disease phenotype.The failure of the immune system to eliminate implanted endometrial cells has been suggested to contribute to the deve...