Y-chromosomal Adam
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In human genetics, Y-chromosomal Adam is the male counterpart to mitochondrial Eve: the last male ancestor from whom all male human Y chromosomes are descended. Unlike other genes, those of the Y chromosome are passed exclusively from father to sons, as mitochondrial DNA seems to be passed to all children only by their mothers.
The Y-chromosomal Adam is the last male ancestor of all humans, tracing only through the male line, through fathers, paternal grandfathers, etc. This is a different concept from the last male ancestor of all humans. That is, if female ancestors are also considered, the most recent male ancestor of all living people may have been (and almost certainly was) a different man, living in more recent times.
Y-chromosomal Adam hypothetically is not the same individual at all points in human history. The last male-line-only ancestor of humans alive today is hypothetically different from the one for humans alive a thousand years in the future.
The Y-chromosomal Adam for living humans probably lived between 60,000 and 90,000 years ago, judging from molecular clock and genetic marker studies. While their descendants certainly became close intimates, Y-chromosomal Adam and mitochondrial Eve are separated by thousands of generations. They are named after the "Adam" and "Eve" in Genesis as a metaphor only, and are not considered to be the first humans. There would have been many others alive at the same time.
Based on DNA analysis as of 2002, both Y-chromosomal Adam and mitochondrial Eve are believed to have lived in Africa, though approximately 85,000 years apart. This is part of the Out-of-Africa theory of human evolution.
See also
- Mitochondrial Eve
- Genetic drift
- Molecular evolution
- Genetic genealogy
- Adam's Curse (book by Bryan Sykes)
- Y-chromosomal Aaron
References
- "Modern Men Trace Ancestry to African Migrants", A Gibbons, Volume 292, Number 5519, Issue of 11 May 2001, pp. 1051-1052.
- "African Origin of Modern Humans in East Asia: A Tale of 12,000 Y Chromosomes (http://www.sciencemag.org/cgi/content/full/292/5519/1151)", Yuehai Ke et al, Science 2001 292: 1151-1153
External links
- The truth about Adam and Eve (http://www.bbc.co.uk/science/genes/dna_detectives/adam_and_eve/index.shtml) (from the BBC)
- Documentary Redraws Humans' Family Tree (http://news.nationalgeographic.com/news/2002/12/1212_021213_journeyofman.html) (from National Geographic)
- Y-Chromosome Biallelic Haplogroups (http://www.roperld.com/YBiallelicHaplogroups.htm)