How Do I Determine the Connection?

Perhaps your results have just come in or maybe you just don't understand how to figure them out!  The fact is that DNA can be confusing but by breaking down the basics into bitesize pieces, it can help you better understand how you are connected to others.  

The testing companies offer up suggestions on how you might connect to another tester but I don't find a lot of accuracy in some of those predicted relationships and use the chart provided by ISOGG.org to help me determine the possible connections.  

Average Shared Autosomal DNA and Relationships 

NOTE: This is not my work, please credit the original source.

Source of table information: http://isogg.org/wiki/Autosomal_DNA_statistics

Solve Your Mystery

Unknown Parentage

DNA tests are often taken by people who want to know more about their family lineage but what happens if your test does not match up with who you believe are your parents or if you are adopted. 

One of the best things that you can do to help solve your mystery of that of someone else, is to create a mirror tree.  In today's youtube video, I offer up suggestions on how to create that mirror tree.   

Build A Mirror Tree from DNA Matches - YouTube 

DNA Ethnicity Estimates

German, Irish or Swedish

Have you heard the story that you have royalty in your family linage?  Or perhaps you have Native American heritage in your blood.  But just how is that determined?  What does the DNA testing services provide in terms of your ethnic background?  

The testing companies are constantly refining their ethnicity estimates based on updated testing.  While I can trace a number of my ancestors to Switzerland and Germany, I seem to show up with more UK in my heritage.  It is important to understand the basics of recombination as well.  A good dose of history is another plus!  

In the end, this is a great "coffee shop" conversation topic.  

Check out this youtube video that I like to call, "How Irish Am I?"  Recombination and Ethnicity - YouTube

Grandparent Connections

How Many are There? 

Just how many grandparents or sets of grandparents do you have?  It depends on how far you can go back in time.  I find that when I am trying to solve a mystery, I need to group people together through the "shared matches" tools provided by the testing companies.  Looking at my results, I find that I often have a number of people who are in common with me and each other but how do I work through this? 

Find the Most Common Recent Ancestor

Finding the shared ancestor between the matches is a GREAT way to narrow down your search but just how many grandparents are there? 

Grandparents

Grouping people together in matched sets will also help you determine the correct connections. But just how many "grandparents" can you expect to find when building your mirror tree?

Cousin	Shared Grandparent	Possibilities
1st	Grandparent	4
2nd	Great Grandparents	8
3rd	Great Great Grandparents	16
4th	Great Great Great Grandparents	32
5th	Great Great Great Great Grandparents	64

 

Understanding Matches on the 23andMe Tool

23andMe Matching

I love the way 23 and Me provides a chromosome browser to help me understand how / where matches share DNA.  Ancestry.com does not offer this toolset.  

This is a clear difference between Ancestry.com and 23andME.  Don't get me wrong, Ancestry has many great features not offered in 23andMe.  MyHeritage and FTDNA have their unique tools that help solve mysteries as well.  

Check out my youtube video which may help you better understand matching on 23andMe.  Understanding Centimorgans and DNA Matches - YouTube 

Autosomal DNA Basics

Finding Family Connections 

Autosomal DNA is one of the best tools we have to find "closer" genetic family matches.  As an example, if you are looking for your ancestor who you believe arrived with the Mayflower, this is not likely going to help you.  But if you are looking to determine a parent, sibling, grandparent and any number of various cousins, this is a great tool to use.  

Recombination

Autosomal DNA follows a somewhat predictable pattern and the fact is that while we inherit half of our DNA from our mother and half from our father, we do not necessarily inherit 25% from each grandparent.  

Check out my youtube video to help get a better understanding of recombination.  I call it the "jelly bean" recombination.  Jelly Bean Recombination Model - YouTube 

DNA Testing Overview

“DNA doesn’t lie”.  That is a common saying among folks who are familiar with using commonly available DNA testing for genealogy.  There are 3 commercially available tests on the marketplace: autosomal DNA (cousin / family finder), Y-DNA (available only to men), mtDNA (available to both men and women to trace maternal lineage).

There are a number of consumer DNA kits but if you are serious about using DNA to find your roots, I have some recommendations:

• Test on both Ancestry.com and 23andMe.com
• Upload your results or test on FTDNA.com and MyHeritage.com
• Upload your DNA to Gedmatch.com

Autosomal DNA

This is commonly referred to as the cousin / family finder test.  It is the test that is administered by Ancestry.com, MyHeritage.com and 23andMe.com. FTDNA also uses this test but FTDNA offers 2 additional test options.

Y-DNA Test 

Remember basic high school biology.  Our gender is determined by the combination of what we get from our parents.  This test is only available for men.   Men are XY and women are XX, meaning that the Y-DNA test can help determine a direct male lineage.

mtDNA Test

Mitochondrial (mtDNA) DNA is passed from our mother from her mother from her mother from her mother …. And so on and so on.  Both men and women can take the mtDNA test but only women pass the mitochondrial DNA to their children. I don't often recommend this test for the purpose of determining family lineage.

X-DNA results

While Ancestry.com does not openly provide your X DNA matches, if you pull your raw data from ancestry.com and upload it to gedmatch.com or familytreedna.com, you may see X-DNA matches.  Men will only get matches on their mother’s side of the tree and women will see inherit matches on both the maternal and paternal line. X-DNA follows a very distinctive path and more about that will come in a future post.

Are you interested in learning more about DNA Basics? Follow me and I'll work to help you understand the nature of DNA as it relates to genealogy research.