Tag Archives: GEDmatch

An open letter to my DNA cousins

Dear Cousin,

I’m so glad to ‘meet’ you through DNA testing! I have lots of family history gems to share and explore with you. Perhaps we can help each other. I have copies of wills and obituaries and photos and maps I can send you–and family lore too!

Since March is the month we celebrate St. Patrick’s Day, I thought I’d offer several Irish examples. (But there’s a Colonial American example at the end too.)

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Is it a maternal or paternal DNA match?

One of the first things we ask about a new DNA match is this: is this a match on Mom’s side, or Dad’s?
We all have two copies of each autosome (i.e. chromosome 1 through chromosome 22): one copy in each pair comes from Mom and one from Dad. Unfortunately, the testing company can’t tell by looking at our DNA if a segment that matches someone else is on our maternal copy of that chromosome, or our paternal copy.
We need to compare our DNA to known relatives who have tested; then we can begin to figure out how our new matches fit in our family trees.
If you’ve had both of your parents take an autosomal DNA test at the company where you and your new cousin match, it’s easy to tell maternal or paternal. But what if you don’t have DNA tests for both parents?
GEDmatch.com has some tools to help us.

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Triangulation with GEDmatch

On 25 Mar 2017, the Central Indiana DNA Interest Group is giving an in-depth presentation on the valuable (and mostly free!) DNA tools at GEDmatch.

At this program, we’ll be talking about the benefits of GEDmatch and walking through how to use the site. Of course, the most Basic perk of GEDmatch is that you can compare DNA from people who tested across different platforms (companies). On an Intermediate level, GEDmatch has tools to help you sort your matches into different lines of your family tree. For participants open to dipping their toes into Advanced territory, we’ll talk a bit about * triangulation *.

I know when I attend webinars or presentations, sometimes my brain gets full and doesn’t process everything I just heard. Then it’s helpful to have a resource to revisit later to help the more complex material sink in. So I thought I’d post something about * triangulation * on my blog this month!

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Chromosome Mapping with siblings – part 1

This month – another post on testing siblings and on using GEDmatch.

Sometimes, having siblings’ DNA tested is a real treat—such as when one of them connects to a distant cousin still residing in Ireland, just a few kilometers from where my ancestors came from. But sometimes—playing with sibling DNA can be a real challenge! Case in point: Chromosome mapping with three siblings. This is advanced stuff, yo.

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I’d like to start off my blog with a big Thank You! I’m very grateful:

  • to my siblings, who agreed to take DNA tests. (And one day I’ll blog about why testing siblings can be a good idea.)
  • to close relatives of my mom and my dad who also agreed to test. It’s so helpful to look at a stranger’s matching DNA and compare it to yours. If it matches you too, then I know which of my parents’ or grandparents’ ancestors will hold the key to our common roots.
  • to more distant relatives that I’ve encouraged to test. Because of you, I’ve developed new leads on what village in Ireland one great-great grandfather came from. Because of you, I’ve found distant cousins of a different race, and we’re exploring which slave-owning ancestor *might* belong in both our family trees. It takes time, but in coming months I’ll probably blog about some of our progress in these or other mysteries and brick walls.
  • to my relatives whom I never knew until the DNA company told us we match. Howdy, cousins! And I want to thank you for replying to my messages or emails, for sharing some of your family history, for helping me in my quest and letting me help you.
  • And finally, to everyone who has agreed to copy their raw DNA data to the free tool at http://www.GEDmatch.com and to the wonderful volunteers who provide that service for all of us ‘citizen scientists’ who are exploring how DNA can help us discover and understand more of our heritage.

Thank you all!

Speaking of GEDmatch… If you haven’t copied your DNA data there yet, here is some information that may help you do so. Many folks have created web pages or blog posts about GEDmatch. I’ll point you to some of my favorites, below.

In a nutshell, here’s what someone new to genetic genealogy needs to know.

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