Homoplasmy
Homoplasmy is the presence of a mutation affecting all of the mitochondrial DNA (mtDNA) copies in a cell. Since there are hundreds or even thousands of mtDNA copies in every eukaryotic cell, mutations may either be present in all copies (homoplasmy) or affect only a fraction of them (heteroplasmy).
See also microheteroplasmy.
Homeoplasmy = a state in which all the mitochondria of a cell or a tissue have the same genome, which may be either the wild type genome or a mutated one.
Homoplasmy may also refer to the presence of mutation, or insertion of a foreign gene, into all of the plant plastid organelles DNA e.g. all of the chloroplasts
Source: adapted by the editor from Wikipedia, the free encyclopedia; from the article "Homoplasmy". Image Credit.
