Evolutionary trees derived from data on mtDNAs. Human mitochondria are maternally inherited, and therefore mtDNA is contributed by the female parent to the next generation. Furthermore, mitochondrial genes do not undergo recombination. For these reasons, it is much simpler to trace mutations in mtDNA than in genomic DNA. In an analysis of mtDNAs published in1987, the restriction fragment polymorphisms were traced back to an mtDNA molecule carried by a hypothetical woman living in Africa about 200,000 years ago. In 1995, comparative studies of the entire mitochondrial genomes from three humans (one each from Africa, Japan, and Europe) and four apes (a chimpanzee, a bonobo, a gorilla, and an orangutan) resulted in the estimate of 143,000 years as the time for the origin of the ancestral human mtDNA, again in Africa. In the popular press, the woman with this ancestral mtDNA is sometimes called “African Eve” or “mitochondrial Eve.” Mitochondrial Eve is our most recent common ancestor in the purely female line. Other women were contemporaries of Eve, but their mitochondria have not been retained, usually because their link with today's descendants is blocked because it passes through a male ancestor. See Chronology, 1979, Avise, Lansman, and Shade; 1987, Cann, Stoneking, and Wilson; 1995, Horae et al.; mitochondrial DNA (mtDNA); contrast with Y chromosomal DNA lineages.
Subjects: Genetics and Genomics.