triangulating a known relationship with unknown matches can reveal the answers. How to do it.
Triangulation is a very broad term with application in many fields, from psychology to politics. In genealogy, triangulation mirrors the process used by surveyors, who employ multiple triangles to help deduce the exact landscape of a particular area. Genetic genealogist creates triangles from groups of three autosomal DNA matches to get a better picture of how each member of the group is related to the others. Commonalities among the three individuals’ family trees may indicate shared ancestors. Example, if two group members have common Williams or Wilson ancestors in Virgina/North Carolina, the third group member – who perhaps haven’t yet reached that far back in their tree – might theorize they are also connected to the Williams/Wilson and turn to traditional genealogical records to investigate. *African-Americans and others of color should be cautious to literally use the triangulations method to prove ancestors. Slavery and forced migration tore families apart and names changed to get rid of the slave owners name for emotional reasons. post traumatic stress disorder among slaves after being freed.
You do not have to be a DNA expert to start using triangulation to your advantage. You just have to have autosomal DNA test results from one of the four major testing companies (23andME <23andMe>, AncestryDNA <ancestry.com/DNA>, Family Tree DNA <www.familytreedna.com>, My Heritage DNA <www.myheritage.com/dna> *Helix is an another company under Geno 2 <www.geno2.com>, a known cousin with autosomal test results, and some shared matches. Now, how the triangulate your way to family tree success.
Read this an many as you need, to get this process down in your mind. School days back again. The triangle used to play music and the triangle giving you fits in math class are very different from Genetic Genealogist’s triangle, there are some definite similarities among them: Without fail, every triangle has three sides, connecting at three points.
Let’s look at each point in the DNA triangle and how to identify it.
POINT A: The first point is you (you’re already a third of the way there!). Always, as you learn in starting your family tree you should start with your self. Well, what makes you the perfect starting point? It’s your DNA of course – your autosomal DNA, the stuff that came half came from your mom and the other half from your dad. Of your enormous DNA record, the testing companies evaluate about 800,000 pieces. A small portion compared to the millions of DNA cells in the human body. Now stop for just a second to appreciate the strength of your position on the triangle. *(Note: If you sequence all of your DNA, most of you would have the tools to really talk turkey with your doctors and maybe they would want to rethink their medical opinion -another story). Your 800,000 pieces of DNA can identify you uniquely, apart from everyone else in the whole world. Not only that but these pieces of DNA also form kind of map of your ancestors and your ancestry. Think of your DNA as various points scattered across time and space, outlining the vast landscape of your heritage. Contained in your own DNA is a record of the places your ancestors lived, their families, and even their secrets.
The trick, of course, is to convert that system of dots into a network of information that you can use to discover your past. This is the greatest strengths of genetic genealogy – the ability to find records that were previously lost. Just as the surveyor uses triangulation of multiple points to discover the contours of a landscape, a genetic genealogist can use the multiple points to triangulate with others and obtain a clearer picture of their own ancestral lines.
Point B: The second point on your triangle is any other person on your match list. Remember, individuals who show up on your match page are there because they share DNA with you. A close genetic match for example 1st cousin twice removed 5th cousin. Now, not all matches are created equal. You want what we’ll call a “Best Match” to occupy Point B on your triangle. Generally, look at the first few pages of your matches.
Point C: With so many possible connections, it’s easy to see why you need a way to narrow your search. This where the third point on your triangle comes in. When you add a third person with his or her genetics and genealogy, you harness the power of triangulation to help you discover which of the eight great great-grandparents or 16 third great-grandparent couples are most likely connecting point for you and your two matches.
This is important for successful Triangulation. To find Point C on your triangle, you need a match with specific characteristics, Point C needs to share DNA with both Point A (you), and Point B (your Best Match). You can find that person most easily using a tool provided by your testing company. The one below is from Shared Matches on Ancestry DNA
“Using shared” Matches at Ancestry DNA, Family Tree DNA “In Common” or 23and Me “Relatives In Common”, there is an excellent chance you the three Points share a common ancestor. Another tool is the triangulation tool on http://www. Gedmatch.com.
Point to remember. Your best matches are the ones who make the best candidates for points on your genetic genealogy triangles. The ones you share the most centimorgans with you. Okay, centiwhats? Centimorgans are how we measure your pieces of DNA.
I hope this is not confusing. There are more points to make and some of them are in the next post right after Centimorgan post.