Y-DNA Testing: Where to Do It, Why to Do It, and How Many Markers to Test - Part 1

Part 1 - Where to Do It

Important update 1/1/16: Although I already recommend the use of Family Tree DNA as the test facility of choice, a recent article on DNAExplained.com has raised serious ethical concerns in my mind about the privacy practices of Ancestry and 23andMe. Please read this before choosing to test through either of those two facilities.

The popularity of DNA testing for genealogical purposes has grown quite a bit over the last decade, with Ancestry.com jumping on the bandwagon and the advent of 23andMe, so I want to talk a little about choosing a testing facility, understanding what the test can and cannot do, and selecting a marker level when you're considering a Y-DNA test.

I only want to address Y-DNA tests in this article since mitochondrial DNA (mtDNA) tests are much less useful for tracing specific lineages. Remember that the Y chromosome is passed directly from father to son, so the Y-DNA test will only give you information about the direct male line of the tester. If you, Mr. Jones, want to find out about the ancestors of your maternal Grandpa Smith, your DNA is of no use in that respect. It may tell you about your Jones line, but it knows nothing at all about the Smiths. You must find a direct-line male Smith cousin and persuade him to test. But I digress...

The potential for using DNA testing to unravel tangled knots of sloppy genealogy and break through decades-old (if not centuries-old) brick walls first dawned on me in 2005 when I became aware of National Geographic's Genographic Project. I wondered how one might go about finding a laboratory that would agree to test my older male relatives, and if I could find such a lab, what I would then do with the results to make any sense of them.

I started poking around online and to my surprise and delight, I saw that Family Tree DNA was already up and running for just that purpose. I quickly ordered three Y-DNA tests: one for my father, a second for my maternal grandfather, and a third for my maternal grandmother's brother. In all three cases, over the last decade, the DNA tests have paid off in spades, connecting me to relevant researchers with proven genetic relationships to the three tested surnames. There have been some surprises, but those are stories for another day. Suffice to say that funds spent on genetic testing have the potential to offer a greater return than those spent on gas and hotels in the fruitless pursuit of records that turn out to be irrelevant at the end of the day.

First to the game, Family Tree DNA (FTDNA) gained an edge with their established surname projects and robust marker-level testing, and they have become the "official testing facility" of National Geographic's Genographic Project mentioned earlier. Their surname projects are often managed by professional genealogists or those who have assumed the position of genealogist for various organizations such as Scottish clans or similar surname or heritage groups. They also offer a number of online learning tools to help testers understand their results, and the value of having access to a surname project administrator with experience in genealogy and DNA results interpretation should not be underestimated.

With FTDNA, there is a focus on the science and the independent collaboration of the testers to understand the implications of their results rather than the building of complex family online trees or providing a workspace for collecting paper documentation. You test, you fill in some basic information about your lineage, you're informed of your matches, you have access to the surname project's results for comparisons to others of the same name, you can communicate with the surname project administrator and your genetic matches, and then it is up to you to work with matching testers and carry your paper research to the next level.

Since I only do tests through Family Tree DNA, I am not in a position to comment on the efficacy of Ancestry.com's process or that of 23andMe, however, there is a DNA blogger who has done a comprehensive comparison of Ancestry vs FTDNA tests, and it appears that there may be enough reciprocity between the results that if you have already Y-DNA tested through Ancestry.com, it is possible to share your results with FTDNA (there is a small charge involved with sharing results, so be aware of that when choosing to test with Ancestry).

The two facilities provide similar marker results (similar - not the same), lists of matches with the ability to contact the matching testers, and tools to help you glean understanding from your results. Ancestry.com is generally agreed to be more user-friendly, but in my opinion, a DNA test should be a serious tool in an arsenal that includes copious paper documentation as well as collaboration with other researches through multiple online genealogical forums, so I prefer to go with the more scientifically robust testing facility that offers the higher test levels and the most cutting-edge tools for analysis. But that's just me. As I said, a level of reciprocity between these two facilities makes Ancestry's results usable for basic comparison with FTDNA's official surname projects, so while I encourage serious genealogists towards FTDNA, I recommend you read the comparison on DNAeXplained and come to your own conclusions.

As for 23andMe, I don't consider it the strongest player in the game of genetic genealogy. There are concerns about the company's "cut-rate genetic testing" that have put it in the hot-seat with the FDA, as well as potential privacy concerns that could trip up unwitting testers. They give top-level, generalized, narrative results (which may include sensitive information about potential health issues), so while that may be of interest to some testers, it is not as useful for cross-referencing marker results with FTDNA or Ancestry.com for family research purposes.

Since I brought up privacy issues, there are a number of misconceptions surrounding privacy and DNA testing, and you should go into the process in an informed manner. I consider FTDNA's privacy practices to be completely reasonable and they address some common concerns on their website. Unlike 23andMe, FTDNA's testing is not designed to give you health information or provide amusing trivia such as "you'd make an excellent surfer" -- the markers are analyzed and interpreted strictly to compare and discern genetic patterns and similarities between testers for the purpose of identifying common ancestors and ancestral origins. DO NOT take a Family Tree DNA (or Ancestry) test to learn if you carry a gene that makes you susceptible to diabetes or cancer - it will not tell you. It does not know.

DNA testing for genealogists is a complex and evolving science. For every absolute there seems to be an exception. Sometimes DNA testing can raise more questions than it answers. Sometimes those questions can be awkward. In some cases the results can rock the foundations of who you think you are. You have to be prepared to accept what you learn. Much of what you can learn depends on the level of testing, and higher marker levels are almost always better (for instance, higher levels can weed out random non-surname matches that can appear at lower levels and turn into time-wasting red herrings). The more we learn, the less certain we seem to become about things we thought we knew. So why do it? And how many markers should you test? I'll cover that in second and third parts this series, so stay tuned.

Continue to next article in series.

For more information on the subject of DNA testing for genealogy, visit FamilyTreeDNA.com's Learning Center. If you have comments that might be helpful to those considering testing, please add them below.