The Genealogy Triangle

There is a revolution going on within researching one’s family tree. Fifteen years ago genealogists used oral history and written records to compile their family histories. Then in the early 2000’s genetic genealogy came on the scene. Things immediately got more difficult to understand with new words like haplogroup, STR’s, SNP’s, and different types of DNA testing, i.e. YDNA, mtDNA and autosomal.


So if you are a member or you are wanting to join the Callen DNA Project what is the progression of testing for your direct male line?

A. Traditional genealogy never ends. The admins of the project are here to help you with your genealogy but I learned it is a mistake to make any bold statements until after initial DNA testing.

B. STR testing. Many people start with 12 marker tests, it is the cheapest test and you can always upgrade later using your provided sample. However it is advisable to upgrade to 67 markers as at that level your non-relatives, that were prevalent at 12 and 37 marker levels have been filtered out. 67 marker testing is considered the “gold standard” for STR testing.

C. SNP testing. With your initial 12 marker test Family Tree DNA will give you a predicted haplogroup usually, R1a, R1b or I haplogroups. Predicted haplogroups in the charts are colored red, while tested haplogroups are colored green. Over the last fifteen years new SNPs have been discovered bringing the age of the SNPs closer and closer to the present times. With the introduction of NextGen testing there has been a literal SNP tsunami of SNPs. The Big Y was first released on the 9th of Nov 2013 and although expensive has been received with great enthusiasm by thousands who have welcomed the new technology. The Big Y looks for all SNPs, known and unknown and usually gives the tester a large group of SNPs that are unique to them. So for the first time SNPs are coming down to written genealogy. STR values can be quite variable and mutate back and forth wile SNPs are a one time mutation.

There are 3 steps in SNP testing:

1 – individual SNPs
2 – SNP packs can have over 100 individual SNP’s
3 – The Big Y tests for thousand of known and unknown SNPs

Please ask an admin for advice on which SNP to order.

So modern genealogy is a tripartite endeavor. We can think of modern genealogy as forming a three sided triangle: traditional genealogy – STR testing – SNP testing.

How is your triangle, are you missing one leg or perhaps even two?


For a more in-depth look at STRs vs SNPs please check out:

STRs vs SNPs, Multiple DNA Personalities from DNAeXplained – Genetic Genealogy



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