Category Archives: DNA

Another way to use this web site

This is a “how-to” post. One way to find something herein is to scroll down the right hand column to the section titled CATEGORIES and select a group out of the drop box.

If the subject you are looking for is not there, you can use GOOGLE SEARCH with the site: parameter. For example, the term CLUSTER in not a category. Go to Google and type “ cluster” without the quotes and your search will find quite a few posts that have the term cluster.

DNA Discussion Group meets Wednesday February 1st

The MoCoGenSo DNA Sig will resume operations, with scheduling like before: First Wednesday of the month at noon via Zoom. Reserve the time in your calendar!

A DNA Discussion Group (SIG) is a group of individuals who have a shared interest in using DNA testing for genealogy and family history research. DNA SIGs typically provide a forum for members to share information, resources, and expertise related to DNA testing and genealogy. Newcomers, beginners, are always welcome!

Please let us know if you would be able to present or share some of the tools or issues you are interested in. Maybe you have a topic or a speaker that you think others might be interested in. Perhaps you can facilitate a meeting. We can all learn from each other.

We haven’t met for 6 months. Lots of things have been happening in the genetic genealogy field in that time. Below are some of the new tools that have shown up at the DNA Painter wed site. Hopefully someone can show us how these things work.

Ancestry . com has not been standing still either. There are many new things that I want to learn how to use. Of course, discussing the Sawtooth Slayer Methodology could easily take a whole session. And I hear that FamilyTreeDNA has not been standing still either. Building clusters is my current pet peeve.

If there is a particular tool or strategy you would like to share with others, or a genetic genealogy problem you would like the group to advise you on, get enough screenshots prepared in advance so you’ll be able to describe the technique step by step on screen, or show us the DNA-related work you’ve already done on your problem case.

My job is facilitator, or door keeper, if you would. Come join us next week. If you can’t make it this month, don’t worry. We plan to be here next month, and the next…

Click to Join Meeting: Zoom Link

Meeting ID: 897 1823 5118
Passcode: 738495

Sawtooth Slayer Method

Having read the book “The Sawtooth Slayer” by Nathan Goodwin, I decided to outline the basic methods used to figure out who was the killer. I really enjoyed the book and don’t’ intend to release any spoilers. But I figure the methodology can be useful for those of us searching for our own puzzle.

In Dec 16, 2012 we posted a search method provided by CeCe Moore which you can see here:

How to catch a killer OR learn more about your ancestry!

I want to compare the methods. I’m guessing that they aren’t all that different, perhaps only terminology differences will appear. The effort might teach me more about the overall procedures. You can work with me, and for sure, email me when I make mistakes. Perhaps we can go over the steps at the next DNA Discussions Group via Zoom.

1. DNA test

In this book, the first thing to do is to have a genetic DNA completed and get it to Family Tree DNA and Gedmatch. The following clustering steps can be done most anywhere, but the book is working with police and FamilyTreeDNA and Gedmatch are the only sites that will allow police involvement.

2. Identify clusters containing unique and in-common-with matches

The clusters are built, manually in the book. You can use auto-clustering at MyHeritage or Genetic Affairs if you wish. Clusters are subsets of the matches that contain unique matches that are in common with each other. Given subset uniqueness, each cluster should have a Common Ancestor (CA) and it is our job to find that person or pair. The book ended up with 7 clusters. Given that there are eight 2x great grandparent sets, that is about right. You start with the highest centimorgan match, select in-common-with, going no further than 10 centimorgans. Call that cluster 1. Go to the next not selected match and build cluster 2.

3. Build a speculative family tree of each person within each cluster, looking for the Common Ancestor

This is where the heavy work is involved. Build the trees at I’m seeing one tree per cluster with floating trees inside per person, because after the CA is located, all the “floats” would disappear. You are building the tree backward in time, going towards ancestors. In the book, they built the trees out to 3x great grandparents. I’m not sure why, that might be difficult in some cases.

4. Triangulate within each cluster, this then “closes” each cluster

I know what triangulate means, common segments for 3 or more people. I guess this step is just to prove that the tree building was legitimate, DNA wise. It will sure provide good documentation. Curiously, the first book in the series didn’t need this to close a cluster.

5. Reverse genealogy (p.230)

Reverse genealogy is where all known descendants of the confirmed common ancestors to the genetic network are traced, searching for the overlap between clusters. This is heavier tree building, building forward in time, sometimes using your “find living people” skills. Following the overlap between clusters should lead directly to the original DNA tester.

6. Success. Contact and adapt!

3rd Party Tools for genealogical genetic testing at DNA Painter

We have previously talked about the free web site called DNA Painter that supports DNA genetic testing with various tools. The most famous tool is called Shared CM Tool.

The site is run in London, England by a guy named Jonny Perl. The site is mostly free, but there is a subscription level which gives you more of many options. For the record, I am a happy subscriber.

There is a free monthly newsletter which is really a useful item which keeps the world updated with news from all around the genetic testing arena. The latest newsletter included an announcement about the new page on the DNA Painter site that contains links to other third-party tools related to DNA analysis for genealogy. This page is a wonderful set of sites that we should all bookmark. And you can leave the updating to DNA Painter!

You can find a link to this new page on the Tool Page at DNA Painter. For now, you can get to it by clicking here:

Mocogenso DNA Group is Paused through 2022

The MoCoGenSo DNA Sig is on hold for the remainder of the year. We will reevaluate its resumption in 2023.

In the meanwhile, there are many great DNA Sigs and Discussion groups throughout the country that are free for the joining. In fact, we have a few right here on the West coast. For example, have you heard of Randy Seaver? He is a long time genealogist who runs a DNA Sig for the Chula Vista Genealogical Society. This link goes to their main page where there is link to the next DNA meeting! Their meetings are via Zoom and are quite interesting. The last one I attended had 32 folks present!

For those who want pure genealogy, Randy Seaver runs a blog that is worth checking out.

And do not forget the Genealogy Society of Santa Cruz County right here in the Monterey Bay area. They also have a DNA Sig that can be found the calendar on their main page at:

Ancestry DNA Ethnicity Estimate has a Sideview

If you have tested your DNA at Ancestry . com, you need to check in with the recently added “Sideview” display that breaks your ethnicity estimates down by your parents, without testing your parents! It is really intriguing and potentially useful for improving the accuracy of your own paper research. I for one didn’t know my maternal side had Welch DNA floating around. I knew about the Irish. When you realize that Wales is only about an hour boat ride from Ireland, you begin to realize that some wily sailor could have joined my ancestors a few generations ago! To see your Sideview, follow these steps.

Go to DNA in the menu bar and select DNA Story

In the Ethnicity Estimate section, select See What’s New

Select View Breakdown

Notice that the two sides are labeled Parent 1 and Parent 2. They can’t tell which half of your genome is which, but maybe you can. Play with the ethnicity sections at the bottom and se if you can decide which side is Mom and which is Pop.

If you can determine “Sides”, like my Maternal has the Irish genes, then select Edit Parents below.

You pick for the Left side. You can always change this later, or even clear and start over.

Once you have chosen sides, you get a nice breakdown like this. Looked at like this, you can see there are subtle differences in my background.

I just wish I knew where that Aegean Islander snuck in from!

Ethnicity Estimates often change, but when they do it is because they are becoming more accurate. I like this new breakdown. When I share this type of data with my family, they seem understand it better than just seeing what my Personal breakdown was. This is meaningful to siblings, cousins, aunts and uncles.

Shared DNA Matches in Ancestry

”They say that our genes create proteins that help define our attributes. Like height, width, etc. And they say that some of these genes correlate with multiple attributes. Like bright teeth and bright eyes. Let me warn you, I ain’t nearly as smart as I look – those genes must not interlace! Shared matches in Ancestry . com prove it, every time!”

Roberta Estes, on the other hand, does seem to understand Shared matches in Ancestry. She wrote a really good blog post the other day all about some of the confusing aspects of Shared matches. Please read her post here as it will explain lots of the confusing details.


Ancestry displays some shared matches with all of your matches, regardless of the size of your match to that person. However, Ancestry ONLY shows shared matches to a third person if you share more than 20 cM of DNA with that third person.

The takeaway of this is if you have a larger (20 cM or over) and smaller match (under 20 cM), always request shared matches from the perspective of the smaller match because the smaller match won’t show up as a shared match on any shared match list. The only way you can see shared matches that includes people under 20 cM is to request to view shared matches with individual people who match you below 20 cM. .

My problem is that I still see shared matches in 2nd/3rd cousin range where Person A links with B & C, but C does not link with A. My intelligence gene folded the wrong direction. (Maybe you can explain it to me in the next DNA Discussion group.)

Rootstech 2022 and the DNA Discussions Group

Rootstech 2022 is happening now.  There are many excellent presentations happening every day covering almost every possible topic relating to genealogy.  The recorded presentations, called Sessions, will be viewable throughout the year. 

The good news is that many of the Sessions from 2021 are still available, the new ones in 2022 are being added to the list!  So you can see last years and this years.

Rootstech has a “Playlist” which are Sessions you have tagged for yourself to watch later.  All you need to do is build the Playlist, and then view them at your leisure.  You still need to sign in to Rootstech to see your Playlist.  Some of the Sessions are in Youtube, you can build a list for yourself to watch later outside of Rootstech, if you wish.

The following description is oriented towards DNA but applies to ANY topic in Rootstech.  

Step 1 – Sign in to Rootstech and Click on Sessions.

Step 2 – Select your topic and select your year. DNA is one of the topics. There are 169 DNA Sessions from 2022, 88 left from 2021, 257 in total.

Step 3 – The list of presentations will be populated on the right. Go through the list and Click on the PLUS sign for those you want added to your Playlist. The Plus sign changes to an X. If you change your mind or after you have watched it, click the X.   This process can take a while! 

Step 4 – Watch the presentations.  Come back whenever, sign in to Rootstech, and Click on the Menu in the top right, then Click on My Playlist at the bottom and “watch on” ! 

I use a laptop with headphones so I can multitask in front of the T-V.  One could use a tablet to watch the videos while using your laptop to follow along in FTDNA or MyHeritage or whatever.

The DNA Discussion group could just watch these all year!  🙂

Download DNA Matches from Ancestry . com

Jim Bartlett is a genetic genealogist who loves to work with spreadsheets. I too like spreadsheets, but he is way beyond me. I follow his blog and always wonder if I should try my hand at building the “master sheet”!

Meanwhile, “clustering” is all the rage now. There are automated methods to build clusters and kindship charts for FTDNA, MyHeritage, 23andMe and Gedmatch. But has decided to not provide a cluster option and as even blocked others from doing so.

The other day, Jim Bartlett posted a method to manually create a clustering spreadsheet for Ancestry! Manually!? I read the post and decided he was a bit crazy. It would take forever to type all those DNA matches I have in Ancestry! Then I remembered that he has a “master sheet” somewhere, and it is probably easy for him to add the cluster-logic.

You can read his article here. This is a must read if you plan to try this. You don’t have to read all of it.

So, I consulted Google and went searching for a method to download all my DNA matches from Ancestry. Google didn’t fail me, I found a spreadsheet that you can copy screens of matches into. It is a special spreadsheet that is loaded with code to scrape data from the DNA match list screens that only works in the Google Docs arena. It helps to have prepared your Ancestry matches ahead of time. It still requires a few hours of work to identify clusters. But it works! I now have 179 matches split into 10 different clusters. Each match has hot links into Ancestry to review trees and add notes.

Using this special spreadsheet is a bit complicated and I am not going to even try to tell you how. The following links do a good job explaining it, good enough for me to make it work. The YouTube is a real how-to video.

I read this but did not use the links here.

This is the YouTube with the instructions that I used. The link to download the spreadsheet can be found in the comment section after the video, click “show more” to see it. But do watch the video first. Click Watch on YouTube below.

Hint: download the sheet, but don’t open it. Just upload it to your Google Docs area and use it there.