What is subclade testing?

Subclade testing can provide increased resolution of your placement on the Y-chromosome phylogenetic tree.  Before your subclade can be determined, you must first know what haplogroup you fall into.  Haplogroups are defined by a unique mutation event such as a single nucleotide polymorphism, or SNP.  These SNPs mark the branch of a haplogroup, and indicate that all descendents of that haplogroup at one time shared a common ancestor.  The Y-DNA SNP mutation has been passed from father to son over thousands of years.  Over time, additional SNPs may occur within a haplogroup, leading to a new lineage.  These new lineages are considered subclades of the haplogroup.  Each time a new mutation occurs, there is a new branch in the haplogroup, and therefore a new subclade.  By testing for the presence of SNPs that have been identified as being indicative of a subclade within a haplogroup, you can now determine which specific subclade you belong to within your previously determined haplogroup.

What are the subclades of Haplogroup G?

Current data suggest that there are at least 19 distinct lineages, or subclades, within Haplogroup G.  These subclades are smaller lineages derived from two Haplogroup G subclades: G1 and G2.  There is also a subclade called G*, but this is often referred to as a paragroup with the expectation that there are likely branches within this subclade that have yet to be determined.  G1 is further divided into three subclades: G1*, G1a, and G1b.  G2 is definitely more complex and can first be separated into four lineages: G2*, G2a, G2b, and G2c.  There have been many distinct subclades detected within G2a, and they can be visualized in more detail in the Haplogroup G Phylogenetic Tree shown below.



Description of the Panel

The Y-DNA Haplogroup G Subclade Test consists of a panel of 11 SNP markers.  These markers are used to define 12 different subclades in Haplogroup G.  The location of the SNP, the actual mutation that is detected, and the subclade that they define is listed below for each of the 11 markers.
 

Description of the Subclades

Since many of the SNP markers that define the subclades withing Haplogroup G have only recently been detected, there have been few studies that have incorporated them into the genealogical analyses.  Consequently, relatively little is known about the individual subclades.  However, this means that any new information gathered about the subclades will be important for advancing our understanding of the history of human populations.  With Haplogroup G, it is expected that further studies will advance understanding of the movement of agriculture into Europe.  The table below summarizes the current knowledge about Haplogroup G subclades.