Existing knowledge of DNA and its application has certainly increased since I learned the fundaments of DNA in high school Biology 11. But it is still true that almost all our cells contain 23 pairs of chromosomes that define who we are: 1 pair of sex chromosomes, and 22 "autosomal" pairs. DNA testing could be deemed sexist due to our inherent biology (girls have 2 X chromosomes, whereas guys have 1 X and 1 Y). We are not all created equal. As I am female and lack a Y chromosome, I am unable to take the Y test. But there are other options.
There is no specific test for the X chromosome yet, and as males also inherit an X chromosome from their mothers, it would not be an exclusive test. But there is a lesser amount of DNA in the cell's mitochondria that is inherited only from the mother, regardless of sex. Therefore mitochondrial (mt) tests can give everyone insight into their direct female line (mother's mother's mother's mother ...). That's interesting, but not very broad in scope for a single individual.
The remaining test looks at a limited selection of locations on all 22 pairs of the autosomal DNA. The testing company then use complicated algorithms to compare your results with others who have also taken this same test. They then provide you with a list of "matches": those who are related to you within 5 generations or so. Each match could be on either your father or mother's side - no way to tell from the DNA alone. And of course it doesn't tell you exactly how you are connected. The only clues you have are surnames optionally posted by you and your matches based on your traditional genealogy research. It's then up to you to contact each match and explore how you might be related. More traditional research is often required to discover exactly how you are connected.
These various tests usually include an estimate of your genetic heritage or "ethnicity", presented in the form of percentages by country or region. They calculate this based on samplings from a variety of population groups in various locations throughout the world where unique mutations have been identified. If your DNA includes some of these mutations, it is probable that your ancestors came from that particular location after the mutation date. We're talking long term here!
For my DNA test, I chose to take the autosomal "Family Finder" test through Family Tree DNA (ftDNA). I ordered the kit at the end of October. After in arrived I did the cheek swab and mailed it back in November. I got word that they had received it in December (it took a while to cross the border and get delivered in the pre-Christmas season). I still didn't have the results by January 14 when I attended another VGS meeting and one of our members talked about her success using the Family Finder DNA test. She discovered and then visited new 5th cousins in the southern USA. The amazing part is that she is white and they are black and they are all thrilled to learn about each other. It was truly inspiring, and I hoped that I would also learn a lot from my own DNA results when they arrived.
The very next day I received an email from ftDNA. My results were now available online! Looking first at my ethnicity, it was no surprise to learn that I am 100% European, including 40% British Isles and 31% Scandinavian (perhaps the Viking influence?). And as far as autosomal matches were concerned, I have well over 200 to review. My top match is a 2nd or 3rd cousin, and from the surnames he listed it seems obvious that we are connected somehow through my father's side. I have a lot of more distant cousins to investigate too.
I had downloaded all the match data into a spreadsheet to make the data easier to view, sort and manipulate. Then when I was browsing through the user names of the submitters (fortunately close or equal to their real names in most cases), one familiar name happened to catch my eye even though it was farther down the list. I thought it might belong to a maternal 4th cousin I had contacted a few years ago, but the person in my match list only used a first initial and had a different email address. And they hadn't listed any ancestral surnames, so it was hard to be sure. So I decided to contact her using her old address to see if she was also the owner of the DNA. I quickly learned that yes, she was the one who had created the DNA account but the DNA sample belonged to her elderly father, who I know is my third cousin once removed (3C1R). The DNA list predicted that the match would be a 4th cousin (3rd to 5th range). So we all got it right!
Obviously I'm just getting started on this big project, hoping to find lots more distant relatives through this DNA process in the months to come. Guess what the primary focus of my research and blog postings will be this year?
DNA Explained, blog
DNA Explained, articles and publications - basic to advanced
Family Tree DNA - Family Finder Autosomal Test overview
Family Tree DNA - How does the Family Finder test work?
Family Tree DNA - FAQs, Autosomal Genealogy Matching