Haplogroup Explanation

Haplogroups

The following information on Haplogroups is given courtesy of David Weston, the Project Administrator of the East Anglia Geographic DNA Group, the creator of this article. Further information may be found at: http://www.geocities.com/thurlowons/eagdna/.

Haplogroups (those letters and numbers) describe where we fit on the human genetic tree. Subclades are the branches or children of the higher branches in the tree. Think of it as your family tree but extending back 60,000-80,000 years for YDNA and 200,000 years for mtDNA. It is the tree that connects all men alive today to our single paternal ancestor known as genetic "Adam" and everyone alive today to single maternal ancestor, known as genetic "Eve".

A branch, called a haplogroup, is created on the YDNA (phylo)genetic tree every time the YDNA of one of "Adam's" male descendents changes or mutates. This mutation is unique and known by the abbreviation SNP, which stands for Single Nucleotide Polymorphism. Every male descendent from that man onwards carries that SNP. Each new SNP is labelled by academics with terms like M91 or SRY10831.1. Some have more than one name. One must refer to the literature to know which is which. The same process applies to the mtDNA genetic tree.

Since we don't know the names of the first of our forefathers to have a given SNP, he is labelled with a letter designation. When one of his male descendents has a new SNP, the letter from his forefather is incremented to the next one in the alphabet or a new letter or number is appended. It is by these letters and numbers that haplogroups identified.

Genetic "Adam" is Haplogroup A. The SNP that identifies this haplogroup is called M91. The haplogroup of genetic "Adam's" male descendents from whom all non-African men are descended, known as "Eurasian Adam", is known as Haplogroup CR and is identified by the SNP M168.

Thus we the genetic lineage of the Project YDNA Haplogroup R1b participants is written as: (defining SNP in brackets)

A (M19) > BR (SRY10831.1) > CR (M168) > F (M89)> K (M9) > P (M45) > R (M207) > R1 (M173) > R1b (M343) > R1b1 (P25) > R1b1c (M269)

As another example, the genetic lineage of the Haplogroup J participants is written as:

A (M19) > BR (SRY10831.1) > CR (M168) > F (M89)> IJ (S2) > J (M304) > J1 (M267) and J2 (M175)

The ISOGG website details the latest known compiled version of the YDNA genetic tree starting from genetic "Adam" down to the youngest known branches.

http://www.isogg.org/tree/ISOGG_YDNATreeTrunk.html

Here is one representation of the mtDNA genetic tree that I found:

http://www.argusbio.com/tools_docs/world_tree7.3.pdf

The National Geographic Genographic Project 'Atlas of the Human Journey' gives an extremely interesting and easy to understand graphic presentation of the evolution and associated anthropological history of both the mtDNA and YDNA haplogroups human genetic trees. I encourage all that have yet to do so to take a look:

https://www3.nationalgeographic.com/genographic/atlas.html

Their Genetics Overview page also provides a better description of haplogroups then I can do here.

Now why should you care about any of these letters and numbers? Because they tell you about your ancestors right back to the first humans and provide a tool to investigate the path that brought you to where you are today. Hg R1b's were amongst the first humans to enter Europe 35,000 years ago. Hg J's were amongst the inhabitants of the eastern Mediterranean shores to first develop agriculture in the Neolithic period completely altering the course of modern human evolution. Hg I1a's were amongst the first Scandinavians that would later become the Norse Vikings and the scourge of coastal Atlantic Europe. And so on,..

As new SNPs are discovered, adding branches to the genetic tree, the hope is we will be able to uniquely identify more recent tribal and ethnic groups like the Angles, Saxons, Danes and others.