"Several attempts at cloning exotic or endangered species have received widespread publicity (e.g. Gaur (Bos gaurus), Banteng (Bos javanicus) and Bucardo (Capra pyrenaica pyrenaica)). The distinguishing feature of these examples is that they employed trans-species cloning (Fig. 2⇓). In these instances, the oocyte cytoplasm being used to create embryos was derived from common domesticated species (Bos taurus (cow) or Capra hircus (goat)), while the cell nucleus was from the species of interest. Trans-species clones inevitably differ from either of the parental species in their nucleo-cytoplasmic characteristics. At the very least, mitochondria inherited from the recipient oocyte would have a major influence over functions, such as muscle development and physiology, that depend on mitochondrial gene expression. Animals resulting from these trans-specific cloning efforts would be scientifically valuable for their insights into the functional relationships involved in nucleo-mitochondria dialogue, but would not be directly useful for supporting the endangered populations."