Genetic Genealogy

Genetic Genealogy is a field that uses DNA match analysis to assist in traditional genealogical document-based research. A DNA genetic test (on its own) is not sufficient to divulge any genealogical information. This is unlike with traditional genealogy and its basis in document research. It is only after comparing one's DNA test result with others, and then correlating that with existing genealogical work, can one begin to extract useful information about family history (simply termed original triangulation).

The field of genetic genealogy requires others be tested, compared to, and have done some genealogical work in addition to yourself. Genetic testing, on its own, is simply determining some characteristics of a persons DNA. A person who practices in this field is termed a genetic genealogist. An early, alternative term used was Molecular Genealogy (as introduced by the Sorenson Molecular Genealogy Foundation or SMGF).

Genetic Ancestry or Deep Ancestry uses similar testing but without the genealogical record analysis. Instead, the comparison is made to populations of people and ancient DNA (aDNA) samples from discovered remains. Also, often long before genealogical records because it involves the study of populations and their movements over tens to hundreds of thousands of years.

Since introduced in 2000, personal genetic testing has greatly expanded in scope while the costs have dramatically fallen. This direct-to-consumer (DTC) testing started around 2000 and initially offered only Y and limited mitochondrial DNA testing; by FamilyTreeDNA and a few others. That was the first wave and supported by basic, simple CE sequencing technology. With the introduction of microarray testing in 2007 by 23andMe, and the dramatic price drop made by them in 2010, the market then exploded. With Ancestry now becoming the "bull in a China shop" when they jumped into the market in 2014. Better, wider-scope testing is constantly being added; as well as better tools to manage the process. Of late, we are seeing a shift from microarray testing to 30x WGS testing (a third wave). Surname Studies, such as this one, are greatly enhanced by all this capability but mostly still rely on Y DNA testing as the foundation in Patriline studies.

There are many types of tests. And lots of methods to do the follow-on match analysis. Which test you take and what analysis you perform depends on what answers you are trying to find. Read each of the subsections referenced below for more details on DNA as it pertains to genealogy, this project, testing techniques, and the very important follow-on match analysis.

Table of Contents (for pages in this section):

In summary, at this time, here is what the project recommends:

1. No matter what your biological sex, if you believe the surname studied here exists in the last 5-8 generations of your ancestors, purchase a 23andMe ancestry-only test for $99 plus shipping (or less). You can find it on their website, Amazon, or even in local stores. This will provide Autosomal, X, Y and mtDNA SNP test results. (yDNA SNP results are only available for males who test.) 23andMe is the only genetic genealogy company to offer this single, all-inclusive below $100 product with analysis. Only more expensive WGS testing will cover all your DNA in one test. (You can order ALL the offered products at FamilyTreeDNA for o lot more money to get all your DNA tested. But with results to a lesser precision than a WGS test that is much cheaper.) Transfer your microarray file format from 23andMe to GEDMatch, MyHeritage, and FamilyTreeDNA to fully utilize autosomal segment matching with DNA relatives and project members.
   
   If you do not care about yDNA and mtDNA SNP testing now, then test with Ancestry as they have the largest match database. Ancestry has very little yDNA, no to little mtDNA SNPs and requires a subscription fee to fully see and connect with matches. Neither Ancestry nor 23andMe support the transfer-in of test results from other test companies (closed databases). They are the largest match databases (often by an order of magnitude) and so testing with both is optimal. MyHeritage is a strong up-and-comer that allows transfers in from all the other test companies and has the most European-resident testers. Ancestry and 23andMe have mostly North American testers but many such testers have recent ancestry in Europe. No vendor is focused on other continents and so the coverage and likely helpfulness of genealogical matching is limited.
   
   
2. If you are a biological male who believes you have a patriline descent from someone with the surname studied here, then additionally order a FamilyTreeDNA yDNA STR 37 Marker test (y37) for ~$120 plus shipping (or less). (If a female, try to find a male relative matching this criteria and have them do this test.) Join your new STR test kit to our FamilyTreeDNA project and your yDNA results will automatically become available for further analysis by project administrators. Ordering as a project member may get you a small discount. We should also note that their Family Finder microarray test is now delivering over 10,000 Y SNP markers. And can sometimes be more defining and the original STR tests of old. That may be a consideration instead of the ((STR) as it is usually a lot cheaper as well.
   
   
3. If wanting to do anything more or different, then email one of the admins for options and variations. Or read the following pages more thoroughly.

For example, to minimize initial money for a male doing yDNA testing, order a FamilyFinder test that now delivers over 10,000 Y SNP markers in addition to the full autosome marker suite. To optimize overall money spent on a male tester and accelerate the results, order the FamilyTreeDNA BigY-700 test. If you do this and do not need the mtDNA test, use FamilyTreeDNA FamilyFinder instead of 23andMe or Ancestry for the Autosomal test to keep it all within one test company and using a single sample. But this is the lowest resolution and smallest match database for autosomes. FamilyFinder can be a good initial test as it now includes the most yDNA SNPs as of 2024.

Also consider that FamilyTreeDNA, MyHeritage and Nebula Genomics use mouth swabs to collect DNA; which work better than spit for those 80 and older or under 10. (All three test kits were from Gene by Gene Ltd, FTDNA's parent company initially even though offered and marketed by different companies.)

Finally, if available on sale, the Dante Labs, Nebula Genomics, YSEQ and Sequencing.com 30x WGS product does test everything any of the above tests do but with much more depth. It can be a one-time, one-stop test for everything BUT will require you to do a bit of work to extract and create the files needed for 3rd party matching services like FTDNA, MyHeritage, GEDMatch, yFull and others. (note: that FTDNA only accepts autosomal upload results and not any Y or mtDNA results. You cannot get into FTDNA's Y match database without testing with them.)

The 23andMe test recommended above does SNP testing of ALL your DNA more than the other vendors. All these genetic genealogy companies are doing microarray testing which is a lower granularity than a WGS test.  

The Autosomal DNA (atDNA) SNP test result (that always includes xDNA SNP results) helps with reliably matching near-term, genealogical time-frame relatives (those with common ancestors to you within the last 200+ years). The Mitochondrial DNA (aka mtDNA) SNP test helps confirm a matriline (female-only) but is only accurate to within the last 5,000+ years (ancient haplogroup). The yDNA SNP test determines the haplogroup for the patriline; possibly within a genealogical time frame of the last 500 years but often farther out.  yDNA SNP testing also often helps distinguish similar value yDNA STR results (false positive) matches that occur when frequently changing yDNA STR values were used for nearer term testing before deeper SNP testing was available. And, after many more tested, found to be more unreliable than SNP testing. But can still be a quick, cheaper alternative to extracting and using microarray yDNA results to confirm a patriline.

We note that Ancestry, FamilyTreeDNA and to some extent MyHeritage are dedicated genetic genealogy companies. With the former two finally, after years of lagging, adding many new features to support the laymen to get more out of the results. This is especially true with Ancestry. FTDNA more for the yDNA SNP result from their BigY-700 test only.

We have flip-flopped between Ancestry and 23andMe as the recommended, first test. And likely will be flopping back to Ancestry. The delay on recommending Ancestry again is the requirement of an expensive subscription to take advantage of their full-set of features. In reality, over the long term, you should test near and far relatives with both companies due to their large match databases and closed environments not allowing transfer in of other company test results. Now that FamilYTreeDNA has decided to add their yDNA SNPs into the FamilyFinder result, it almost makes this route appear the best. But that test still lacks mtDNA testing and is the smallest match database of the dedicated genetic genealogy testing companies.

The second test, yDNA STR, is the initial way a male participates in this and other surname studies to try and match similar males in the genealogical time frame and farther back in time.  Both the yDNA STR and SNP tests may be needed for males to truly verify the patriline (male-only lineage) family branch. Different levels of testing accuracy exist for yDNA (as explained in our Y DNA Markers page) and a deeper (more marker) test may be needed depending on factors not determinable until you test. A WGS test covers all yDNA testing to a depth exceeding any other test; except some STR markers are not determinable. Microarray testing not only helps anyone find genealogical time frame relatives (via the autosomal result) but can be a way for someone to verify they belong to a patriline branch (by matching autosomal with a yDNA tester in that patriline). The project can assist you in with analyzing yDNA test results contained within most microarray SNP testing company results (offered by all except FTDNA). Or simply use Cladefinder and do it yourself.


We further encourage you to view the Momondo "Your DNA Journey" viral video from 2016. Many take the microarray tests from Ancestry and 23andMe simply for the ethnicity pie charts and ignore the cousin matching databases. That on its own can be very informative for the laymen not working in genealogy; especially not that it is more accurate.

External References

• Direct to Consumer Genetic Testing Primer from the National Library of Medicine, part of the US National Institute of Health
• Genetic Genealogy testing science explained article in Vox from May 2019 (good at introducing why identical twins tested on the same site and different sites show such different results in ethnicity estimates)
• Cyndi's List of DNA Blogs: A great resource for current news and information; often from leading speakers
• ISOGG Wiki: Have made a dramatic push; expanding the content and removing the extreme biases exhibited earlier. Tends to lag behind the industry in perceptions and advances though. And does get things very wrong sometimes. We had hoped to avoid developing our material and sections here. But found they were just too wrong, and too lagging, to be a useful primary source. Not that we get it always right either. But we methodically learn and improve. With that said, is the most comprehensive single source for genetic genealogy.
• Discovery of unexpected paternity after direct-to-consumer DNA testing and its impact on identity, 5 Aug 2022

See Also

• Autosomal and X DNA testing
• Y DNA Patriline testing
• Mitochondrial DNA Matriline testing
• Waves of Genetic Genealogy test methods available over time
• Generations of Sequencing testing available over time
• Glossary of terms