The present invention provides induced pluripotent stem (iPS) cells generated from a mitochondrial disease patient with a mutation in mitochondrial DNA, which exhibit a bimodal degree of mutation heteroplasmy, namely mutation-rich mitochondrial disease-specific iPS (Mt-iPS) cells which have increased mutation frequencies and mutation-free Mt-iPS cells in which the mutation frequencies decreased to undetectable levels. Also provided is a method of producing the mutation-rich and mutation-free Mt-iPS cells, as well as a use of the former as a source of model cells of mitochondrial diseases and a use of latter as a source of cells for autologous transplantation therapy.
