From: Heritage Daily
A newly discovered chromosome places the most recent common ancestor for the Y chromosome lineage more 100,000 years before the oldest known anatomically modern human fossils.
UA geneticists have discovered the oldest known genetic branch of the human Y chromosome the hereditary factor determining male sex.
The new divergent lineage, which was found in an individual who submitted his DNA to Family Tree DNA, a company specializing in DNA analysis to trace family roots, branched from the Y chromosome tree before the first appearance of anatomically modern humans in the fossil record.
The results are published in the American Journal of Human Genetics: http://www.cell.com/AJHG/abstract/S0002-9297(13)00073-6
Our analysis indicates this lineage diverged from previously known Y chromosomes about 300,000 ago, a time when anatomically modern humans had not yet evolved, said Michael Hammer, an associate professor in the University of Arizonas department of ecology and evolutionary biology and a research scientist at the UAs Arizona Research Labs. This pushes back the time the last common Y chromosome ancestor lived by almost 70 percent.
Read the full article at: heritagedaily.com