Thursday, December 30, 2010

The Gene Tree, Haplogroups


Haplogroups are defined by their single nucleotide substitution called a SNP (snip). [single nucleotide polymorphism] Those in the know [researchers who have established the system of naming [nomenclature] have assigned an English alphabetical system starting with the letter A. This haplogroup is felt to be the oldest genome surviving since our earliest days. The figure to the right is my attempt at showing a "big picture" of this classification system. The dates generally believed to be starting points for each branch of this gene tree are given along the top ridge for each haplogroup. More than 60,000 years ago the human race is believed to have shared a common genetic message. At around 50,000 years ago the human genome started to branch, giving rise to several new DNA messages. Down through the ages, each branch developed a new haplogroup, passing its single nucleotide polymorphism down to the next generations. As time passed, these branches became the roots of our ethnic and cultural family groups. My JONES DNA is haplogroup R1b, believed to have branched from haplogroup R1 some 25,000 years ago. It was around this time that the earliest human burial has been described on the island that was to become my family's home. [The "Red Lady of Paviland" on the Gower Peninsula.] What a deal!

2 comments:

  1. Thanks for the time you took to put together this graphic. I find it much easier to visualize this way.

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  2. E1b1b is closer to 25,000 - 28,000 years old. See Underhill, Cruciani, Hammer, etc. or just check the Wiki entry. the next downstream SNP (E1b1b1) is over 22,000 years old.

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