#$%^&*AU2010200421B220120216.pdf#####ABSTRACT The present invention provides tissues derived from animals, which lack any expression of functional alpha 1,3 galactosyltransferase (alpha-1,3.GT). Such tissues can be used in the field of xenotransplantation, such as orthopedic reconstruction and repair, skin repair and 5 internal tissue repair or as medical devices.