If you have taken a Family Finder test, the MyOrigins section will show you what percentage of your DNA is African and European. At a later stage you can upload your DNA data to Gedmatch and analyse it more specifically from an African point of view with a variety of different biogeographical analysis tools. 

Also, you will have a variety of different matches and you may be able to shed new light on your ancestral origins by contacting them and sharing what you know about your family tree - they may have some information that will help you break through some Brick Walls.

If you have taken a Y-DNA test, there are several possible results that you could get, including unexpected results. Before testing, you should go through each possible result on the list below and ask yourself "how would I feel if I got this result?". If you feel you could accept each result, only then should you take the test.

One important thing to remember is that if you have been passed down an Irish surname by your ancestors, and you identify as "being Irish" as a result, then you ARE Irish, no matter what the DNA test results say (or anyone else for that matter). YOU determine your own identity, not a DNA test.

Here is a list of the possible results - it is not comprehensive but it will give you an idea of what to expect.

1. your Y-DNA results indicate that your genetic signature is ... probably Irish
2. ... more likely to be African, not Irish
3. ... more likely to be Asian, not Irish
4. ... more likely to be European, but probably not Irish
5. ... probably Irish, but it could also be British or European
6. your Y-DNA results ... do not match anyone in the database
7. ... do match people in the database, but no one with the same surname
8. ... closely or exactly match people in the database with the same surname

And here are some possible explanations for each scenario:

1. Your genetic signature is ... probably Irish
   There are certain genetic signatures (or haplotypes) that occur more frequently in present-day Ireland than anywhere else in the world. Whilst this is not conclusive evidence of an Irish connection it is highly suggestive of one. Put another way, the chances that your Y-DNA came from somewhere else may be very remote indeed. The science of ancient migrations and population genetics is making huge strides at the moment and the next few years will probably see major scientific breakthroughs in this area.
2. Your genetic signature is ... more likely to be African, not Irish
   With every project, there is always the chance of an NPE or Non-Paternity Event. This simply means that the transmission of Y-DNA down the direct male line (from father to son) has been interrupted at some stage. There are many possible causes for this including adoption, children adopting their mothers name, sharing out children to be raised by relatives, births out of wedlock, legal name changes, and ancestors taking on the surnames of the plantation owner. If your genetic signature is more likely to be African, this could indicate that there was an NPE somewhere along your line, or that your Irish surname was bestowed upon your ancestors by a plantation owner. An African genetic signature suggests that your Y-DNA has been passed down from someone who lived in Africa within the last several thousand years, rather than in Europe or elsewhere. This will take you on a whole new journey back to Africa and the Project Administrator will guide you to projects that will help you continue this journey.
3. Your genetic signature is ... more likely to be Asian, not Irish
   An Asian genetic signature suggests that your Y-DNA may have been passed to you from the Native Indians of the Caribbean (such as the Caribs or Arawaks).
4. Your genetic signature is ... more likely to be European, but probably not Irish
   According to admixture tests, the average African American is 65-80% sub-Saharan African, 19-29% European and 0.6-2% Native American. In many cases the presence of European DNA is likely to reflect the widespread sexual exploitation of women during slavery and forced breeding with white men. This is supported by the fact that when we look at Y-DNA in particular (on the direct male line), 35% of African American men have European Y-DNA. Interestingly, 3-4% of "white" people have been found to have "hidden" African ancestry (including myself). There are various projects that will help you explore where your European DNA came from.
5. Your genetic signature is ... probably Irish, but it could also be British or European
   Many of the genetic signatures or haplogroups found in Ireland are also quite common in the UK and continental Europe, so it may be necessary to do further testing to see if it is possible to refine your haplogroup even further (i.e. further testing might identify your signature as being more likely to be specific to Ireland). This is an evolving science and the next few years will see major leaps forward in determining ancestral migrations within Ireland, Britain, and Europe.
6. Your Y-DNA results ... do not match anyone in the database
   You may have a very rare genetic signature that doesn't match anyone because no one else with the same signature has taken the test. An example of this happened in 2012 when the Y-DNA results of an African American man rewrote the genetic history books.
7. Your Y-DNA results ... do match people in the database, but no one with the same surname
   This is a common finding for all DNA testing participants. It could simply mean that not enough people with your particular surname have been tested. Nevertheless, it may still be possible to draw some useful conclusions from your results. If many of your matches have Irish surnames, these could be descendants from a common ancestor to you all who did indeed live in Ireland, but PRIOR to the introduction of surnames (i.e. more than 1000 years ago). This information can be used to help pinpoint or confirm the location of your Clan Homeland, using the methodology developed by Dr Tyrone Bowes of IrishOrigenes, who can prepare a personalised report for you if you wish. In addition, it may be possible to make contact with local communities near the Clan Homeland and encourage them to test local people with your surname.
8. Your Y-DNA results ... closely or exactly match people in the database with the same surname
   This probably means that you and your match shared a common ancestor within the last 1000 years. The closer the match, the more likely that you and your match are recent genetic cousins. The next step is to make contact and to try to establish if there is any family lore or even documentary evidence of family members going to the Caribbean. This collaboration may lead to important discoveries about the local history on both the Caribbean and Irish sides.

Maurice Gleeson, August 2014