Ooplasmic transfer: problems and prospects.
Cytoplasmic transfer between human oocytes, which represents a complete cytoplasmic exchange, has been performed recently as a means to improve the outcome of assisted reproduction and becomes a hotspot of researches. Many studies have indicated that mitochondria in the oocytoplasm obviously affect fertilization of the oocytes and early embryo development. However, ooplasmic transfer can lead to mitochondrial DNA heteroplasmy and the prospect of mitochondrial heteroplasmy and its potential problems necessitate further studies. The authors reviews the ooplasmic transfer, the relation between ooplasm and fertilization and embryo development, and the mitochondrial heteroplasmy. The authors also propose a new theory of "reverse cloning technique".