DNA: X Marks the Spot

This is Part 3 in a series of post dedicated to finding out more information about your DNA test results from 23andMe or Family Tree DNA. If you haven’t read it, yet, view Part 1 or Part 2.

I had the YDNA and mtDNA down pretty good in my head. One is paternal, one is maternal, and so on. Then after I submitted my info to GEDMatch,  I saw the “Compare your X-chromosome FTDNA or 23andMe result with one other result in our database” option. Ok, so what exactly does the X Chromosome tell me and how do I inherit it?

The X Chromosome is passed down by both parents, though only daughters get it from their father as the father sends over the Y Chromosome to their son instead. This makes for a weird line of inheritance through your ancestry. A good way to figure this out is to use a fan chart. I was able to find a chart on this helpful post over at The Genetic Genealogist about the X Chromosome. Here is my chart, filled in with my ancestors, telling me where I could have inherited my X Chromosome:

Click for larger

Click for larger

The charts can be found over at The Genetic Genealogist, though I had to increase the image size a bit to make it easier to work with. There is also a chart showing the estimated percentage of the X Chromosome that you get from each ancestor.

I obviously don’t have all of the boxes filled in as I don’t have those ancestors figured out, yet. On my research over at GEDMatch, I see that I match a few people on my X Chromosome. So, in theory, these people would be related to me through those ancestors in the chart above (or beyond, in the same sequence.) My French-Canadian ancestry is included in the chart above, so I undoubtedly will have a lot of connections through there as I always do. It’s not a silver bullet by any means, but it does help you narrow down your search if you find a connection, especially along with other matches in other DNA areas or common surnames.

Again, there is another very quick and helpful video on the X Chromosome over at the University of Utah’s Molecular Genealogy page. I would definitely watch it.

Next time we will talk about the other 22 Chromosomes or the Autosomal DNA.

 

About Brian Zalewski

I started genealogy research about mid-1999. My grandfather had passed away in April of that year. Since then I’ve done a lot of research not only for myself, but for friends and other relatives. In 2006, I married the love of my life, Darcy, and welcomed the birth of our daughter, Aerissa Jean, in 2010 and our son, Xander Lee, in 2012. I can’t wait to tell them stories about all of their ancestors.

Additional Resources

A Featured Post

Famous Milwaukeeans

Milwaukee was the birthplace and home to a few famous individuals. People who have shaped our world with their entertainment and their creations. Here are some of the people from the Milwaukee area. There are comedians, brewers, socialist mayors and even a Prime Minister. Take a trip back with some of these famous individuals as […]