Methods for mitochondrial DNA replacement in oocytes

A method for producing an oocyte in vitro comprising the steps of:

• (a) enucleating a recipient primate oocyte from a first primate without a mitochondrial disease in a manner that does not lower levels of maturation promoting factor (MPF), wherein the primate oocyte is enucleated using a non-UV-based spindle imaging system;
• (b) isolating a karyoplast comprising chromosomes from nuclear donor primate oocyte arrested at metaphase II from a second primate with a mitochondrial disease
• (c) introducing the karyoplast into the enucleated recipient primate oocyte, wherein introduction of the karyoplast is performed using a fusogenic agent, wherein the fusogenic agent is Sendai virus, and wherein the first primate and the second primate are from the same primate species, but wherein the first primate does not have the mitochondrial disease, thereby producing a hybrid oocyte that is arrested at metaphase II;
• (c) fertilizing the hybrid oocyte in vitro to produce a one-celled embryo;
• and
• (d) culturing the one-celled embryo in vitro to form a two-, four- or eight-celled embryo, a morula or a blastocyst embryo.