Using DNA Segments to Find or Verify Ancestors
It’s exciting to have new DNA analysis tools continually developed by amazingly smart and creative people! Hybrid AutoSegment is a brand-new 3rd-party DNA tool from Genetic Affairs. This tool gathers DNA segment data from 23andMe, Family Tree DNA, My Heritage, and GEDmatch together in one report. Having the segment information all in one place streamlines the process of examining, analyzing, and figuring out which of our DNA segments we inherited from specific ancestors. Now, we don’t have to compare segment data between computer files or manually import the data from different testing companies into one massive spreadsheet.
Some DNA Basics
As you know, the autosomal DNA we inherited from our ancestors was recombined and reassembled each generation. We have 23 pairs of chromosomes. Twenty-two pairs are autosomes, numbered 1-22, and one pair is the sex chromosomes, XX for women and XY for men. We have two copies of each autosome, one that we inherit from our father and one we inherit from our mother.
This diagram illustrates DNA inheritance with one chromosome.
Each generation inherits about half of the previous generation’s DNA and passes on about half of what was received. You inherited 50% of your DNA from each parent, who, in turn, inherited 50% of their DNA from your grandparents. The DNA recombines in each generation, and the portion you receive is a random mixture of the DNA passed down from your ancestors. You receive around 25% of your DNA from your grandparents, 12.5% from your great-grandparents, 6.25 % from your great-great-grandparents, and 3.125% from 3rd great-grandparents, and so on.
The various colored pieces in the diagram represent segments of DNA. These are the segments that we can examine on each chromosome. We can’t visualize our own DNA segments, but we can look at them compared to the DNA segments that our relatives have inherited.
I wanted to visualize the DNA segments shared between my known family members and our DNA cousins that share the same ancestors. I tried the hybrid AutoSegment analysis tool, and I’ll share the process of how I entered DNA account data and how I used it in a genealogical research project.
First, I opened my account on Genetic Affairs, and this initial page opened.
Initial page on Genetic Affairs after logging in.
I selected “Run Hybrid AutoSegment,” and the next page opened.
Run Hybrid AutoSegment page
There is a tutorial explaining how to gather the DNA match and segment data from MyHeritage, Family Tree DNA, GEDmatch, and 23andMe. (AncestryDNA does not report segment data. To see AncestryDNA data, you need to transfer the raw DNA results to FTDNA, MyHeritage, or GEDmatch.) It is helpful to have taken a DNA test or upload raw DNA results to all DNA testing companies to connect with all possible DNA matches.
However, you don’t have to have DNA at each of the companies; you can just load the files from the companies you use. The analysis costs $1. After you have loaded the needed files, click on “Perform Hybrid AutoSegment Analysis,” and the report will be generated and emailed to you.
Combining DNA and Traditional Genealogy Research
As part of the Family Locket Research Like a Pro with DNA Study Group, I am using DNA and traditional genealogy to verify the genetic connections between 6 generations of my family tree. I am fortunate to be able to use the DNA results from my great-aunt (I’ll call her Jane) to verify the biological connection to my 4th and 5th great-grandparents. If possible, it is helpful to use the DNA results from relatives who are one or two generations closer to the ancestors we are researching. This is because they share more DNA with the descendants of our more distant ancestors.
I have been drawing a vertical pedigree chart using Lucidchart, including Jane’s DNA matches and charting their descent from our common ancestors. Two of Jane’s DNA matches had posted their family trees in the Family Tree DNA database. Using their published family trees, I was able to identify the common ancestors that we share. In the FTDNA chromosome browser, I could see the DNA segments that Jane shared with her two matches, and I wanted to see who else shared those same segments of DNA.
Working with the hybrid AutoSegment Reports
I excitedly downloaded and extracted the data from the zipped file, which arrived in my email within a short time. The first folder I saw was labeled “AutoSegment.” After opening that folder, the following files were shown:
I double-clicked on the top file, and it opened in my Internet browser. After looking at the faint colored clusters, I scrolled down to see the next section, which had a chromosome browser and an interactive table listing the DNA matches and shared DNA segments.
There are two ways to search for DNA matches in the hybrid AutoSegment files from Genetic Affairs. The first is to look in the Excel AutoSegment document, and the second is to search the interactive table.
Excel file with a list of the DNA company or GEDmatch, DNA matches sorted by overlapping segments, the amount of shared DNA, and the number of the cluster created by Genetic Affairs.
I zoomed out so far that the colors don’t show in the spreadsheet, but the colors are shown on the left side. The clusters indicate DNA segments from DNA matches that overlap each other at specific locations on the chromosomes.
The same Excel file with a zoomed-in view
I searched the hybrid AutoClusters Excel file for the names of the DNA cousin matches (Tester 2 and Tester 3) that share common ancestors John Killian and Lydia Ann Hopper, and their daughter, Letha Jane Killian with me.
Genetic Affairs grouped Tester 2 in cluster 235 and Tester 3 in cluster 73. I went back to the hybrid AutoSegment file and opened the folder with the “chromosomes” HTML files. After choosing file 235, I clicked to open it and saw a chromosome browser and an interactive table. The table contains a zoomed-in view of the people and the shared DNA segments in a specific cluster. The table lists the DNA matches and the segments they share with Jane and possibly with each other. I say possibly because it is unknown if the DNA that Jane shares with the people on the list is on her maternal or paternal copy of the chromosomes where her cousins share the DNA segments.
Explanation of AutoCluster Chromosome browser
The description under this heading says:
“A chromosome browser allows users to perform a graphical comparison between one or more matches to see how much DNA the user shares in common with them. Before we visualize the shared DNA segments, we perform clustering to group segments that are overlapping. Next, these segment clusters are visualized using a certain color. In addition to the graphical representation, a table is available that contains the detailed information for the segment clusters.”
AutoSegment clusters 73 and cluster 235
It was easy to see the colored sections of the chromosomes where the shared DNA segments are located. Scroll down to see the interactive table.
The blue lines represent the DNA segments that Jane and her matches share. One hot tip is that the column headings can be expanded by hovering over the area between the columns. When the cursor turns into a line with arrow points on each end, click and hold the mouse and move it to the right or left to see more or less of the column heading. Each of the fields can be sorted.
The next thing I did was open the DNA company website listed next to the matches’ names. I searched for the names in the segment list and looked for family trees attached to their DNA accounts. There were no public family trees for the DNA matches in cluster 235 available, so I sent messages to the DNA matches asking for permission to view their private family trees. I hope that the family trees are large enough to include our common ancestors, John Killian and Lydia Ann Hopper.
Next, I moved on to Jane’s 2nd Family Tree DNA match, Tester 3, that shares our common ancestor one generation closer, Letha Jane Killian. The list showed a segment shared between Jane and Tester 3 on Chromosome 18 with a start point of 20,639,454 and an endpoint of 54,418,559. Twenty-three additional DNA cousins share the same or an overlapping segment of DNA in the same location.
One of the people on the list had an extensive family tree and shared our common ancestral couple, John Killian and Lydia Ann Hopper! The other people in the list sharing a portion of chromosome 18 either had small family trees or no family trees. I will need to write to them and learn more about their ancestors. I may need to build their family trees to verify the connection to our common ancestors.
I’ve heard that a good rule of thumb is that for each generation in the family tree, the same number plus one DNA matches need to be identified to confirm the connection. For example, 4 [generations] plus one = 5 DNA matches to verify the connection to Letha Jane Killian and 5 [generations] plus one = 6 DNA matches to verify the connection to John Killian and Lydia Ann Hopper.
I’m excited about using hybrid AutoSegment to quickly see the DNA matches that share DNA segments with me. Having the data in one location will simplify visualizing DNA segments. It will also help me identify the ancestors that DNA matches and myself or Jane have in common.
Give hybrid AutoSegment a try, it may be just the tool you need to make some accelerated progress in your genealogy research!