ADAM2 and male infertility: Chen et al. (1999) predicted the contribution of ADAM2 to the mediation of the sperm-egg membrane interactions by its bounding of the integrin α6β1 receptor of oolemma with an assisting CD9 protein. An evident role of ADAM2 in the fertility of males was suggested by a study that involved the deletion of ADAM2 gene in the mouse sperm, which led to male infertility due to impaired sperm migration inside the female reproductive tract and decreased the ability of sperm to merge with the oocyte (Cho et al., 1998).