New approaches to dating suggest a recent age for the human mtDNA ancestor.

The most critical and controversial feature of the African origin hypothesis of human mitochondrial DNA (mtDNA) evolution is the relatively recent age of about 200 ka inferred for the human mtDNA ancestor. If this age is wrong, and the actual age instead approaches 1 million years ago, then the controversy abates. Reliable estimates of the age of the human mtDNA ancestor and the associated standard error are therefore crucial. However, more recent estimates of the age of the human ancestor rely on comparisons between human and chimpanzee mtDNAs that may not be reliable and for which standard errors are difficult to calculate. We present here two approaches for deriving an intraspecific calibration of the rate of human mtDNA sequence evolution that allow standard errors to be readily calculated. The estimates resulting from these two approaches for the age of the human mtDNA ancestor (and approximate 95% confidence intervals) are 133 (63-356) and 137 (63-416) ka ago. These results provide the strongest evidence yet for a relatively recent origin of the human mtDNA ancestor.

[1]  P. Goldberg,et al.  ESR dates for the hominid burial site of Es Skhul in Israel , 1989, Nature.

[2]  James E. Hixson,et al.  Comparisons of ape and human sequences that regulate mitochondrial DNA transcription and D-loop DNA synthesis , 1988, Nucleic Acids Res..

[3]  C. Stringer,et al.  Genetic and fossil evidence for the origin of modern humans. , 1988, Science.

[4]  A. Wilson,et al.  Mitochondrial DNA sequences in single hairs from a southern African population. , 1989, Proceedings of the National Academy of Sciences of the United States of America.

[5]  J. Stephens,et al.  Methods for computing the standard errors of branching points in an evolutionary tree and their application to molecular data from humans and apes. , 1985, Molecular biology and evolution.

[6]  H A Erlich,et al.  Generation of single-stranded DNA by the polymerase chain reaction and its application to direct sequencing of the HLA-DQA locus. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[7]  S. Sherry,et al.  Geographic origin of human mitochondrial DNA revisited , 1992 .

[8]  M. Stoneking,et al.  Geographic variation in human mitochondrial DNA from Papua New Guinea. , 1990, Genetics.

[9]  D. F. Roberts.  The Colonization of the Pacific , 1992 .

[10]  M. Nei.  Molecular Evolutionary Genetics , 1987 .

[11]  M. Stoneking,et al.  Rate of sequence divergence estimated from restriction maps of mitochondrial DNAs from Papua New Guinea. , 1986, Cold Spring Harbor symposia on quantitative biology.

[12]  J. Chappell,et al.  A 40,000 year-old human occupation site at Huon Peninsula, Papua New Guinea , 1986, Nature.

[13]  P. Bellwood.  The colonization of the Pacific : some current hypotheses , 1989 .

[14]  Rhys Jones,et al.  Thermoluminescence dating of a 50,000-year-old human occupation site in northern Australia , 1990, Nature.

[15]  K. Hawkes,et al.  African populations and the evolution of human mitochondrial DNA. , 1991, Science.

[16]  W. Steiner.  GENETIC VARIATION IN HAWAIIAN DROSOPHILA VI. SEASONALLY‐DEPENDENT GENE CHANGES IN DROSOPHILA MIMICA , 1979, Evolution; international journal of organic evolution.

[17]  S. Horai,et al.  Intraspecific nucleotide sequence differences in the major noncoding region of human mitochondrial DNA. , 1990, American journal of human genetics.

[18]  F. Tajima.  Statistical method for testing the neutral mutation hypothesis by DNA polymorphism. , 1989, Genetics.

[19]  B. Greenberg,et al.  Intraspecific nucleotide sequence variability surrounding the origin of replication in human mitochondrial DNA. , 1983, Gene.

[20]  A. Wilson,et al.  Sequence Evolution of Mitochondrial DNA in Humans and Chimpanzees: Control Region and a Protein-Coding Region , 1991 .

[21]  T. Jukes.  CHAPTER 24 – Evolution of Protein Molecules , 1969 .

[22]  N. Saitou,et al.  The neighbor-joining method: a new method for reconstructing phylogenetic trees. , 1987, Molecular biology and evolution.

[23]  M. Ruvolo,et al.  Geographic Origins of Human Mitochondrial DNA: Phylogenetic Evidence from Control Region Sequences , 1992 .

[24]  R. Trent,et al.  An Asian-specific 9-bp deletion of mitochondrial DNA is frequently found in Polynesians. , 1989, American journal of human genetics.

[25]  M. Stoneking,et al.  Human origins and analysis of mitochondrial DNA sequences. , 1992, Science.

[26]  M. Stoneking,et al.  Population variation of human mtDNA control region sequences detected by enzymatic amplification and sequence-specific oligonucleotide probes. , 1991, American journal of human genetics.

[27]  A. Di Rienzo,et al.  Branching pattern in the evolutionary tree for human mitochondrial DNA. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[28]  L. Jin,et al.  Variances of the average numbers of nucleotide substitutions within and between populations. , 1989, Molecular biology and evolution.