Actually, I think Mslynx is referring to
Mitochondrial DNA.
Mitochondrial DNA (mtDNA) provides a valuable locus for forensic DNA typing in certain circumstances. The high number of nucleotide polymorphisms or sequence variants in the two hypervariable portions of the non-coding control region can allow discrimination among individuals and/or biological samples. The likelihood of recovering mtDNA in small or degraded biological samples is greater than for nuclear DNA because mtDNA molecules are present in hundreds to thousands of copies per cell compared to the nuclear complement of two copies per cell. Therefore, muscle, bone, hair, skin, blood and other body fluids, even if degraded by environmental insult or time, may provide enough material for typing the mtDNA locus. In addition, mtDNA is inherited from the mother only, so that in situations where an individual is not available for a direct comparison with a biological sample, any maternally related individual may provide a reference sample.
Present day archaeology continues to be in conflict with the relative newcomers, the biochemists, who claim to be able to date the origins of present-day humans from various molecules to be found in the cell, one of which, mitochondrial DNA (mtDNA) is the subject of this article.
Archaeologists currently date the earliest assumed finds of modern man, Java Man and the Chinese fossils at 1,000,000 and 750,000 years before present respectively. In contrast, the biochemists quote values of 140,000 to 290,000 years before present to trace all mankind back to a single female, dubbed `Mother Eve'. This `tracing back' of the family tree has been done by studying living individuals from several populations and examining the differences between their mtDNA. These differences will have built up over the past generations by miscopyings, mutations, during reproduction. Further to this, recent work with mice, which is thought to be applicable to humans, suggests that these dates could be roughly halved because of evidence that mtDNA can be contributed by the father in about one case in every 1,000.
