Tuesday, January 19, 2021

The Story of Bernadette - Part 12: Uploading to Other DNA Databases: GEDmatch

DNA helix strands
Time was running out for Bernadette. She was now in hospice and no longer communicating with me. My next viable option in searching for her true birth parents was to upload her raw DNA file from AncestryDNA to other databases in the hopes of finding a closer match.

I contacted Bernadette’s son and received permission to download her raw file. Having access to her DNA file would provide more options in our search. Since a tester owns their own DNA results, testing companies make it easy for kit owners and managers to access and download DNA data to a ZIP file. This file can then be uploaded to other databases. In order to do genetic research for Bernadette, I had been assigned the role of manager for her kit, allowing me the ability to download her raw file.

Many NPEs are unaware that by testing with just one company, their matches are limited to only that particular company’s database. Unlike a decade ago, today there are many choices for autosomal DNA testing – and therefore many databases where a match can be found. If an NPE is serious about locating their birth family, they should make sure their results are in as many databases as possible, hence casting a wide net for DNA matches.  One way to do this is to download a raw file from your initial DNA test and upload it to other databases without having to retest.

But not all DNA testing companies allow you to upload a raw file from a different company to their database. Some will only accept testers who have purchased and completed a kit through their own company. Nevertheless, there are several options that welcome raw file uploads.

My first and most obvious choice was GEDmatch, an online service created to help others compare DNA results. Founded in 2010 long before the home DNA test craze took hold, GEDmatch is not a testing company. It is an online universal database where anyone can voluntarily submit DNA results from any testing company with the hope of finding genetic matches. Not as large as the AncestryDNA database, GEDmatch was originally used as the best way for NPEs and birth parents to find each other no matter where they were located or with whom they had tested.

It was a simple process to upload Bernadette’s raw file to GEDmatch. And in a short period of time, I was able to view her DNA matches. I kept my fingers crossed and hoped for a close connection.

Scanning the long list of DNA cousins I recognized a number of surnames associated with Bernadette’s paternal and maternal lines. This was not helpful as we know most of these surnames came from an endogamous community and they overlapped all four of Bernadette’s grandparent lines. 

Disappointingly, Bernadette’s closest match in the GEDmatch database shared only 43 cMs between three segments. This was a very distant cousin relationship, somewhere between a 4th and an 8th cousin - too distant to be of help. It was obvious there were no new clues to be had at GEDmatch to help with our DNA search.

Undaunted, I moved on to our next option.


DNA double helix

Photo Credit: Dmitry Sunagatov



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