 embodiment, the transgenic cells, tissues, organs and animals expressing the functional recombinant xcex0GalA are transgenic pig cells, organs, tissues and/or animals. Second, the present invention relates to methods for xenotransplantation comprising introducing the transgenic cells, tissues and/or organs into human recipients so that a lower level of hyperacute rejection (HAR) is observed in the human recipients relative to the level of HAR observed in human recipients having received non-transgenic cells, tissues and/or organs. The invention is demonstrated by way of the Examples presented in Sections 0-00, below, which