Tag Archives: genetic genealogy

Down the DNA Rabbit Hole – DNA Painter

My latest DNA obsession is the online program DNAPainter. To be honest, I’ve been hearing a lot of great things about the program for awhile, but hadn’t wanted to venture into these waters. Because I just knew, once I did, I would fall deep into this rabbit hole.

The purpose of DNA Painter is to map chromosomes, using shared segment data from one’s matches. The program accepts data from several sources, including Gedmatch, 23andme, and familytreeDNA. AncestryDNA data is not usable since the company does not provide a chromosome browser. A match would have to transfer their raw data file to Gedmatch or familytreeDNA first.

As a highly visual person, I like to see how all the different segments I share with my relatives line up. This is especially useful when tracking triangulation groups. Entering data into the program can be time consuming—depending on how many matches one has. I chose to import data from only known relatives at first. I wanted to see how much data I had and if I already had some triangulation groups forming. Below is a screen shot of my chromosome 7. As you can see, I already have a lot of data for this chromosome.

Chromosome 7

The purple bars on my paternal chromosome all belong to relatives on my paternal grandfather’s side—the Yegerlehners and Schieles. Based upon the members of the purple group, I can assign this group specifically to the Schiele side. The small purple segment on the far right belongs to a distant Yegerlehner relative. The red bars are matching segments I have with my paternal grandmother’s side—the Fosters and Lawheads. The first red bar on the left can be attributed to my ancestral couple George Rea and Sarah (Jewell) Rea; and, the longer red bars to James B. Foster and his wife Lydia (Dicks) Foster.

Since I have matching segments with a variety of relatives, it is easy to see where my recombination points occur. There are three recombination points on my paternal chromosome—at about 14 cM, 103 cM, and 152 cM. Compared to the visual phasing that I did between my brother’s DNA and my own last year, the two charts align well together.

Two-sibling visually phased chromosome 7

DNA Painter has many great features, such as the ability to see all the members of a shared group, or how a specific individual matches the profile person. Matches can be assigned to either the maternal or paternal side of the family, or even to an “I don’t know” group if the relationship is unknown. Matches who share more than one set of common ancestors can have each individual segment assigned to different ancestors. Groups can be named or color-coded to the user’s preferences. For my preliminary profile, I used color-coding based on my four pairs of great grandparents. If you haven’t tried playing around with DNA Painter yet, I highly recommend it. There are many great features that I continue to discover as I work with the program, and I have barely mentioned a fraction of them in this review. Happy mapping!

©2018 copyright Deborah Sweeney
Post originally found: https://genealogylady.net/2018/01/23/down-the-dna-rabbit-hole-dna-painter/

Down the DNA Rabbit Hole – More Visual Phasing with Two Siblings

[Editor’s note: Several months ago, I wrote a post on visual phasing, or chromosome mapping, with two siblings. That post can be found here.]

Phasing is the task or process of assigning alleles (the As, Cs, Ts and Gs) to the paternal and maternal chromosomes. The term is usually applied to types of DNA that recombine, such as autosomal DNA or the X-chromosome. Phasing can help to determine whether matches are on the paternal side or the maternal side, on both sides or on neither side. Phasing can also help with the process of chromosome mapping – assigning segments to specific ancestors. The use of phased data reduces the number of false positive matches, particularly for smaller segments under 15 centiMorgans (cMs).

—ISOGG wiki

In my quest to map the chromosomes of sibling pairs (vs. sibling trios), I turned towards phasing kits on GEDmatch earlier this summer. In order to use this technique, at least one parent must have been DNA tested. Since both my parents have tested for me, I was able to use their results to create phased kits for my brother and myself. To phase a kit, use the GEDmatch phasing tool.

Image courtesy of GEDmatch

After I created phased kits for my brother and myself, using the one-to-one comparison tool, I compared the maternal kits against one another, and then the paternal kits. As a result, the crossover, or recombination points, for each chromosome are clearly delineated. Because only one chromosome from each pair is being compared, the colors are different from a standard one-to-one comparison. We see purple on the top bar where my brother and I share DNA. Red indicates where no DNA is shared. Likewise, on the bottom bar, dark blue shows where DNA is shared, and grey where it is not.

Maternal phased chromosome 13

Paternal phased chromosome 13

Because the kits are phased, I can see which crossover point belongs to which parent, instead of having to spend the extra time deducing—maternal vs. paternal.  Afterwards, I assign the segments based upon collected data from close relatives.

Unassigned segments for chromosome 13

Every time I obtain new segment data, I record it in my master spreadsheet. I place only the data from known relatives in this spreadsheet. By known, I mean the lineage is documented and I know where the person fits into my tree. None of this data is speculative. Below are my brother’s and my matches for chromosome 13. We have plenty of good matches on chromosome 13 due to several of our father’s first cousins having tested. Additionally, two close relatives from our maternal side—who share segments on chromosome 13—also tested for me. A sprinkling of third and forth cousins assist in the mapping as well.

Segment data for chromosome 13

My brother and I share a segment with my father’s paternal cousin S.Y. I continue with the Yegerlehner segment for much of my paternal chromosome. My brother has a crossover point (31) and can be seen sharing with my father’s maternal cousin J.R. for the bulk of his paternal chromosome. Around the crossover point at 92, I begin to share with some more distant cousins on my paternal grandmother’s line. While at the end of his paternal chromosome my brother crosses over to where he inherited a Yegerlehner/Schiele segment.

On the maternal chromosome, my brother and I share part of the McGraw/Kerschner segments. However, I match some New England cousins from my maternal grandmother’s line.

Chromosome 13 – Mapped between two siblings

I continue to collect data where I can. One thing to remember about mapping (like all genealogy research) is that new data may affect how we interpret all the data. I recently discovered that I had misattributed a segment shared with a 1C1R (and it was throwing off how I had assigned a segment on my map). It was a small segment, and I assumed because he was a known relative it was a real segment. It turned out that once I analysed this segment with my mother’s kit, they did not share this segment at all! So either the small segment I shared with my 1C1R was a false segment (a random alignment of DNA), or we have another common relative on my paternal tree. Happy mapping!

©2017 copyright Deborah Sweeney
Post originally found: https://genealogylady.net/2017/10/03/down-the-dna-rabbit-hole-more-visual-phasing-with-two-siblings/

Jamboree 2017

 

Last week I attended my third Jamboree, the Southern California Genealogical Society’s annual conference, in Burbank, California. This year I crossed the imaginary divide and became a speaker as well. On Saturday morning, I presented one lecture, Dating Fashion in Photographs, and then sat on a panel The Next Generation: Young Genealogists and Your Society. As usual the conference was a blast. The committee did an excellent job making everyone feel welcome. And in one case, when a session was too full, the speaker gracefully consented to give his talk again later that same evening.

 

Divided into two parts, Jamboree begins with a separate DNA day on Thursday, then continues Friday thru Sunday with a wide variety of lectures and a full lineup of vendors in the exhibition hall. I generally arrive Wednesday afternoon and leave sometime Sunday morning. Over the course of this year’s Jamboree, I attended seventeen sessions, one banquet with keynote speaker Debbie Kennett, and the NextGen meetup. I hosted two ProGen meetups, sat in the Author’s Nook, gave one lecture, and participated in a panel discussion. Most importantly, I connected with old genealogy friends, and made a lot of new ones. At home, I have few opportunities to connect with fellow genealogy enthusiasts and professionals in person. It was wonderful to talk about genealogy and share family stories, without people’s eyes glazing over. I’m sure you know what I mean!

NextGen Panel: Eric Wells, Deborah Sweeney, Lisa Medina, Melanie Frick, Randy Whited, Paul Woodbury (Photo credit: Victoria Wells)

Various ProGen members, including Blaine T. Bettinger, Patricia Stanard, Lisa Gorrell, Mike Bronner, Jill Morelli, Dennis VanderWerff, Jane Neff Rollins, Janice Lovelace, Annette Burke Lyttle, Janice M. Sellers, Elissa Scalise Powell, and me (Deborah Sweeney).

Knitting in the hotel lobby Wednesday before the conference began

I always like to hang out in the lobby when I arrive in Burbank. It’s a long day for me since I drive from Northern California. It’s a great way to find old friends and make new ones. Plus I usually get some knitting done, like this sweater.

Melanie Frick and I

This year I didn’t get to spend as much time with fellow genealogist (and panel leader), Melanie Frick. But we found time to take our annual photograph.

 

Blaine T. Bettinger and I

Blaine and I spent 18 months in the together in the ProGen Study program. We always take a reunion photo! Maybe someday we can convince the rest of our group to come to Jamboree as well!

Ready to speak first thing Saturday morning!

My session was packed! Over 60 people came to hear me speak. Audio of my presentation is available through the Jamboree website.

James M. Baker, CG and I

While hanging out at the Author’s Nook, I was able to meet Northern California’s resident certified genealogist (CG), James M. Baker. It was great to finally meet him in person, instead of just hearing about him.

I spent a couple evenings hanging out with a fantastic group of genealogists, including Lauren McGuire, Lara Diamond, Debra Dudek, Brad Larkin, Mark Hammond, Jon Nedry, and Blaine Bettinger. After a LONG day attending sessions, it was great to sit back enjoy their company.

If you have never attended an all day genealogy seminar or conference, I encourage you to do so. Conferences provide a wonderful opportunity to learn new skills as well as to network with other genealogists. Stay tuned this summer for an exciting announcement and a new series of blog posts.

©2017 Deborah Sweeney
Post originally found: https://genealogylady.net/2017/06/18/jamboree-2017-2/

Down the DNA Rabbit Hole – Mitochondrial DNA

A few weeks ago, I wrote how the X-chromosome and mitochondrial DNA are different. Both have unique inheritance patterns but they are not the same thing, not by a long stretch. Many people are not familiar with mitochondrial DNA as it is not the most popular, or well known, of the DNA tests. However, everyone has mitochondrial DNA which they inherited from their mothers which makes this type of DNA a great tool for solving some DNA mysteries.

While yDNA is passed down from father to son, mitochondrial, or mtDNA, is passed down by a woman to all of her children. While male children inherit their mtDNA from their mothers, males cannot pass it down to their children. Only female children pass down mtDNA. Both yDNA and mtDNA are passed down for many generations without mutation unlike autosomal DNA which recombines with every new generation. These two types of DNA testing are great for ancient ancestry, going back hundreds of years.

The mitochondrial inheritance line through a child’s mother’s mother’s mother.

In my own research, I have only tested the mtDNA of one person, my father. I chose to do this test because I have a brick wall ancestor in his maternal line:

David, my father
Gladys (Foster) Yegerlehner, my grandmother
Emily “Emma” H. (Lawhead) Foster, my great grandmother
Margaret A. (Rea) Lawhead, my 2X great grandmother
Sarah A. (Jewell) Rea, my 3x great grandmother

Eventually I hope to use the information from my father’s mtDNA to discover (and confirm) who Sarah A. (Jewell) Rea’s female ancestors are.

Going down the tree from Sarah, there are only three living people in my immediate family who share this mtDNA – haplogroup H1g1 – my father, his first cousin, and her son. My grandmother only had male children with my father being the sole surviving child. My grandmother also had a sister, hence my father’s female first cousin and her son. Once they are gone, I will have no immediate family members who share this mtDNA. Margaret (my 2X great grandmother) had two daughters. However, her second daughter’s only child was a son; the mtDNA was not passed down beyond her grandson, Roscoe, on that line. Potentially, Sarah has living descendants with her mtDNA; she had two daughters, Margaret and Jane. Jane had four daughters, three of whom had daughters, and so on. Sarah’s direct female descendants will share the same mtDNA.

Potential mtDNA carriers from Sarah (Jewell) Rea

I currently have 234 mtDNA matches at FamilyTreeDNA; only four are perfect matches with zero (0) mutations. Since mtDNA mutates very slowly, even though I have four perfect matches, I have not been able to determine how these matches are connected to my family. Our most common recent ancestor (MCRA) likely lived hundreds of years ago.

To solve my brick wall, I can sit and wait for another “perfect” match to test their mtDNA and hope that we can find the connection, OR I can do some targeted testing. Even though I have no direct evidence of who Sarah’s parents were, I have a lot of indirect evidence. And if you have been following along, you KNOW I have already traced the collateral lines of Sarah’s potential siblings, especially her sisters. I might even have a direct female descendant (or two) that might be worth pursuing to see if they carry the same mtDNA.


Two of the best modern examples (and my personal favorites) of genetic genealogy forensics using mtDNA are the mysteries Richard III and the Romanov family:

Richard III
http://www.smithsonianchannel.com/videos/can-spit-prove-this-skeleton-is-king-richard-iii/21591

Romanov family
http://genetics.thetech.org/original_news/news108

©2017 Deborah Sweeney
Post originally found: https://genealogylady.net/2017/05/30/down-the-dna-rabbit-hole-mitochondrial-dna/

Down the DNA Rabbit Hole – Second Cousins

A few weeks ago I noticed a new cousin in my father’s match list at AncestryDNA. The new match was the top person in the third cousin category, an “extremely high” connection sharing 189 centimorgans (cM) over 8 segments. Based on the averages from The Shared cM Project  (version 2.0) graph, my father’s newly discovered cousin landed squarely between a range of second cousin (2C) and second cousin once removed (2C1R).

Using Ancestry’s “shared matches” tool, I discovered that our new cousin (whom I will call Fred) also matches my father’s two first cousins on his maternal side, as well as a couple extended cousins on the Foster side of the family. At this point, the additional shared matches have allowed me to narrow down which branches of the tree I should explore. I do these steps before I ever try to contact a match. I like to have an idea of how I am connected to a new cousin to increase the likelihood of having a productive correspondence. How many of us have received generic queries such as “I don’t have any of those surnames in my tree” or “How are we related?” Doing preliminary research saves time and frustration later.

Since Fred matches my father’s first cousins, I checked to see how many centimorgans they share with him. Cousin A shares even more than my father does: 264 cMs across 8 segments. Cousin B shares considerably less: 46 cMs across 4 segments. Such is the randomness of recombination! However, if I average the amount of shared DNA between these three first cousins, the amount is 166 cM. The amount still falls between the average ranges of 2C and 2C1R.

Armed with my growing excitement and an arsenal of data, I contacted Fred. He responded within twenty-four hours! A miracle! And then, I learned, Fred was adopted at birth. He knew only sketchy details of his origins, including the city where he was born. I have heard that some people shy away from matches once they learn a person is adopted, however I provide all the assistance I can. I knew Fred was connected to a specific branch of my family, and relatively closely. Based upon Fred’s information and his DNA test, it is likely that my family was a paternal match, not maternal. If Fred was possibly a 2C or 2C1R, I needed to determine who the potential males of my family tree were at these ranges.

Finding the Second Cousins

Most of us know who our first cousins are. For me, it’s very simple. I can count them all on one hand and still have my thumb left over. I am a little sketchy on how many second cousins I have without my family charts in front of me. I’ve never actually counted them! Both my parents had plenty of first cousins, resulting in many more second cousins for me than first cousins. Going further back up the tree, I needed to know how many second cousins my father actually has. In order to help Fred solve his mystery, I needed a firmer grasp of my tree. For Fred, his DNA was a small needle in a very large haystack. He had no idea where to begin looking to solve his puzzle. Whereas I had several clues and a very narrow field of possibilities.

My father’s second cousins on his maternal side

It turns out that my father has twenty-seven known second cousins on his maternal side. This type of research falls under the category of collateral line research, in my opinion, since one must trace all the descendants of a targeted pair of ancestors. Because Fred’s shared amount of DNA with my immediate family falls between the range of 2C and 2C1R, I also had to consider that Fred was likely the child of one of the second cousins, making him a 2C1R. Fred is closer to my age than to my father’s, so there is a potential generational difference between Fred and my father.

Some Foster relationships in comparison to Fred

Since I did not find any likely candidates for Fred’s father amongst my father’s second cousins, I tried to find as many of their children as possible. This generation would be my third cousins or my father’s second cousins once removed. They were a little more difficult to find as many were born after the 1940 census, but other records (like obituaries) became more useful. So far, I have identified over twenty-five cousins in this group. Of these, one male fits all the criteria, including being in the right place at the right time, to be Fred’s potential biological father. Granted I haven’t tracked down all of the cousins in this group, but I feel fairly confident that we have found a highly probable candidate.

In the future we have several options including: sitting back to wait and see who else tests (just this morning a new known 2C1R on this branch of the family popped up), or be more proactive and solicit one of Fred’s potential half siblings to test.

©2017 Deborah Sweeney
Post originally found: https://genealogylady.net/2017/05/16/down-the-dna-rabbit-hole-second-cousins/

Down the DNA Rabbit Hole – Collateral Lines

Many years ago when I first began my genealogy journey, one of the first strategies I learned about was collateral line research. For some people, the primary purpose of their genealogy research is to learn about their direct ancestors. Who were they? What did they do? Some researchers never move beyond this phase of investigating their family’s stories. To be clear, there is nothing wrong with this approach. We all research (or don’t research) our family history for different reasons. For myself however, I wanted more. I strive to learn not only my direct ancestors’ stories, but who else populated the vast tapestries of their lives.

In the short hallway of my grandparents’ house in Centerville, Indiana, hung two handwritten family trees, one for each of my grandparents. My grandfather’s tree had one female ancestor named Mary. She was the wife of Jacob Troxell, an early settler of Fayette County, Indiana. I descend from the only child Jacob and this second wife, Mary. They both had children from their first marriages, and I can imagine Jacob and Mary’s rowdy household that included a dozen children, aged twenty something to infancy, in 1843. Sadly, Mary died in 1844 when my 2X great grandmother, Sara Ann, was one-year old. Because Sara was so young when her mother died, there wasn’t much information passed down about Mary. She became a launching point for me, or in other words, a reason to dive deep (and wide) into a rabbit hole. The only way I was going to learn more about Mary (and her branch of my family tree) was to follow her other children. In other words, to learn more about Sara Ann, I had to trace the lines of her older half maternal siblings.

Fast forward twenty plus years later…

My diligent research into the collateral lines of Sarah, Mary, and countless other ancestors, has proved extremely useful for my 21st century DNA research. When we find DNA cousins in our match lists, at a very basic level, these cousins are descendants of the collateral lines in our family trees. A common hurtle I have repeatedly had to overcome with DNA matches is the direct ancestor goggles. How many of us have matches with two surnames or perhaps only four surnames posted on their profile? Matches who have only searched their tree up (direct), and not out and down (collateral) may not be familiar with ALL the surnames that are connected to their tree. A direct line surname can change very quickly, especially with daughters marrying into other families. To combat the frustration of finding matches with limited trees or knowledge of their ancestry, I have turned to my database of collateral line research.

For many years, I tried to establish a link via traditional paper research from my ancestor Alfred M. Dicks to an Alfred Dicks in Guilford County, North Carolina. With the addition of DNA, I had a new tool to establish a connection. Through the estate documents of Nathan Dicks, who died intestate in 1833, I had a complete listing of Nathan’s minor children: Achilles, Alfred, Cornelius, Elizabeth, Esther/Hester, Rachel, Mary, Nathan, and Lydia.

Guilford County, North Carolina, Orphan’s Court, Petition of Eleanor Dicks, widow of Nathan, November 1833

With the exception of Rachel and Nathan, the remaining seven children had large families. If we assume my Alfred M. Dicks was the same man as the Alfred named as a child of Nathan and Eleanor, the following list shows their names, spouses, and number of children:

  • Achilles, m. Sarah Ann Frost, lived in Clark Co., IL – eleven children
  • Alfred, m. Ruth Reynolds and Nancy Hamilton, lived in Crawford Co., IL – eight children
  • Cornelius, m. Eunice Blackburn, lived in Guilford Co., NC – twelve children
  • Elizabeth, m. Alfred Story, lived in Guilford Co., NC – five children
  • Hester (Esther), m. Levin G. Ross, lived in Guilford Co., NC – five children
  • Rachel, m. Hugh A. Wiley, died soon afterwards
  • Mary, m. Eli Hanner, lived Randolph Co., NC – nine children
  • Lydia, m. William A. Weatherly, lived Indiana – eleven children
  • Nathan, died young

Since Alfred and his siblings were born between 1815 and 1830, and they had sixty-one children between them, by the early 21st century, they collectively and potentially have a lot of descendants with many different surnames!

Generation One

Dicks

Generation Two

Dicks
Story
Ross
Wiley
Hanner
Weatherly

Generation Three

Dicks
Story
Ross
Wiley
Hanner
Weatherly
Lemay
Green
Cooper
Lindley
Davis
Welborn
Fogleman
Foster
Ball
Kinney
Ferree
Glass
Hurley
Knight
Jones
Mendenhall
Harrah

In three generations, a single surname from  Nathan and Eleanor (Leonard) Dicks has increased to twenty-three possible surnames between their descendants, all before 1900. Imagine how many surnames there are in 2017!

Another tip to remember: Just because your direct ancestor did not leave the county or state where they were born, does not mean their children stayed there. Of Nathan and Eleanor’s nine children, three of them (Achilles, Alfred, and Lydia) left the south and migrated to Indiana/Illinois.

I recommend tracing out as many lines as possible to increase the likelihood of recognizing collateral surnames. When you are done, you can write a family history! So okay, maybe that’s just me…I love writing ancestor descendant lineages.

Over the years, I have found many online trees for DNA matches. Time and again, the trees are one or two generations short of our shared ancestor. By becoming familiar with all the descendants of a targeted ancestor, you will increase your potential for discovering the connection with a DNA match.

Using the Collateral Name List

My father has a fourth cousin match on 23andme. There is no tree, but the match provided a list of sixteen surnames.

Fourth cousin match, 23andme

Fourth cousin match’s surname list

Because I had done extensive collateral line research on the potential family of Alfred M. Dicks, I recognized the surname Hanner. Alfred’s sister, Mary, married Eli Hanner. I was able to focus additional research on Mary’s family. I knew how our families were connected when I contacted the match. It made for a much more productive and positive conversation. Additionally, since finding this match, descendants of Achilles and Lydia, as well as another Hanner cousin have all DNA tested. They match my father and me, further confirming a DNA link to Nathan and Eleanor (Leonard) Dicks, and proving that Alfred M. Dicks of Crawford County, Illinois, and Alfred Dicks of Guilford County, North Carolina, were the same person. Of course it didn’t hurt that I finally found a document naming Alfred M. Dicks and Achilles Dicks of Crawford County, Illinois, as grandsons and heirs of William Dicks, Nathan’s father…

© 2017 Deborah Sweeney
Post originally found: https://genealogylady.net/2017/05/09/down-the-dna-rabbit-hole-collateral-lines/

 

Down the DNA Rabbit Hole – Visual Phasing with Two Siblings

Visual phasing of two siblings, a method of chromosome mapping, is possible with the assistance of first, second, and more distant cousins. The methodology of this technique is very similar to three-sibling visual phasing. One of the biggest differences is how segments are assigned to the four grandparents (two maternal, two paternal). For more in-depth coverage of the three-sibling technique, Blaine Bettinger’s five part series on Visual Phasing is essential (see links below). This how-to assumes that the reader has basic knowledge of the three-sibling technique. The following is a condensed version of how I visually phase my chromosomes using my brother’s DNA in comparison with my own DNA.

In the beginning, I used Microsoft Word for my mapping. The process was clunky, and I moved on… I mention this step because there are various programs one can use to achieve the same results. Feel free to use the program that works best for you!

Lars Martin published a fabulous how-to YouTube video on using Excel to map chromosomes. There is no volume (so don’t worry!).

Instead of having three bars comparing each of three siblings to each other, my visual phasing only has one (since I am only comparing myself to my brother). Using Lars Martin’s method, my blank frame looks like this. In the example below, I have already filled in the recombination points and drawn the lines and boxes. To find the numeric recombination points on Gedmatch, both the “Graphics & Positions” button and the “Full Resolution” button must be checked when viewing a one-to-one match. (see diagram 1)

Diagram 1

The other key factor in visual phasing with only two siblings is having close family members, generally at the first and second cousin relationship. But any known cousin relationship will work. Parents will not work, nor will immediate relatives beneath the generation being phased. For example, my first cousin’s son will not work because I can not differentiate his DNA between our set of shared ancestors. He descends from both of my grandparents as well. First cousins can also be tricky because they share one set of grandparents with the siblings being phased.

I use an Excel spreadsheet to keep track of my close as well as more distant established cousins. For each chromosome, I keep track of which relatives match my brother or me, recording the start and end points of each segment that is shared. Paternal cousins are on the top of the chart while our maternal matches are at the bottom. The example shows our matches for chromosome 13. (see diagram 2)

Diagram 2 – Excel spreadsheet showing matches on chromosome 13

The Paternal Chromosome

Next, I begin to fill in the segments like a giant logic puzzle. I could start anywhere on the chromosome, but I have started on the far right. Between recombination points 108 and 114, my brother and I share nothing. We inherited different segments from each of our four grandparents. Luckily we have data that shows who inherited which segment from whom. I also created a color key for each of my grandparents.

Jack shares a segment from cousin 1C1R – RG between 108-114 on the paternal chromosome. I did not. 1C1R – RM belongs to the Yegerlehner side of the family so this segment is colored green. Since I did not inherit the Yegerlehner segment, my segment is colored blue for the Foster family. On the maternal chromosome, since Jack inherited a segment from the McGraw side of the family while I must have the Leonard segment. While I share several segments with my second cousin MM, I do not share this segment. So logically, I must have a Leonard one. (see diagram 3)

Diagram 3 – End segments colored

For the next portion, I am moving on to the green blimp between points 28 and 31. The bright green on the top line of of the chromosome comparison indicates that my brother and I share the same segment on both our paternal and maternal chromosomes. We share the same paternal segment with 1C1R – SY, in this case, another Yegerlehner segment. My brother stops at point 31, while I continue to share the segment with 1C1R – SY for a little longer. From approximately point 33 through 104, Jack has a series of matches with cousins on the Foster side of the family. Since he does not have recombination points at either 33 or 104, I have extended this segment from recombination point 31 to recombination point 108. (see diagram 4)

Diagram 4

Since I do not match any of the Foster relatives until recombination point 92, I continue my green bar until point 92. At this point, my paternal chromosome recombines, and I begin sharing the Foster segments. (see diagram 5)

Diagram 5

To complete the last part of the paternal chromosome, I color both green. Yegerlehner cousin 1C1R – SY begins matching us at point 21. Since neither of us have a recombination point there (point 21), our segments are extended to the beginning of the chromosome. (see diagram 6)

Diagram 6

The Maternal Chromosome

Jack and I each share part of the same segment with maternal cousin 1C2R – RS. My segment begins at recombination point 28 and continues past point 50. Jack’s segment begins before point 28 but ends at point 50. I extend Jack’s segment to the beginning of the maternal chromosome. On my maternal chromosome, I extend the McGraw segment to point 73.

Looking at points 0 through 28 and points 50 through 73, I observe the blue and grey bars on the Gedmatch one-to-one chromosome comparison as well as the yellow top bar. The Gedmatch colors tell me that from points 0 though 28, Jack and I match on only one chromosome. We have segment data from a paternal cousin which we both share. Logically, this indicates that Jack and I do not have matching segments on our maternal chromosome. If Jack has part of the McGraw segment, then I must have inherited the Leonard one. Similarly, from points 50 through 73, Jack and I do not share any segments in this part of the chromosome. I share part of the McGraw DNA so my brother must share the Leonard side. (see diagram 7)

Diagram 7

The last section of the maternal chromosomes is completed with a combination of shared segment data and more logic. From points 73 through 89, Jack and I must share the same maternal segment. Gedmatch indicates that we share a half-region, and we do not share our paternal chromosome. We also have distant cousins 5C1R – AF and 5C1R – MG who share segment data with us. Even though these are distant cousins, our maternal grandparents came from different regions of the country so it is unlikely there is intermingling of these two branches of our tree. The paper trail also verifies the match. Jack stops sharing the segment at recombination point 89. From points 89 through 92, I do not share any DNA with Jack. From 92 through 108, we already share our paternal segment, so we must have different maternal segments. I continue to share with maternal cousin 5C1R – AF on the Leonard branch of the family while Jack shares part of his maternal portion with a McGraw cousin. (see diagram 8)

Diagram 8

And voilà! Chromosome 13 is mapped, only 22 more to go!

Chromosome mapping with only two siblings is highly dependent on matches with accessible segment data. Sometimes it takes time to find that one cousin who will provide the segment data you need. Just be patient! All it takes is one spit at a time…and possibly a lot of tenacity, and a little bit of bribery.


Blaine Bettinger ‘s Visual Phasing blogs:

Part I

Part II

Part III

Part IV

Part V

©2017 Deborah Sweeney
Post originally found: https://genealogylady.net/2017/05/02/down-the-dna-rabbit-hole-visual-phasing-with-two-siblings/