Testing my history - mtDNA

Now that we've discussed the basic idea about genealogical DNA testing (if you don't know what I'm talking about refer to the last post "It's Pretty Amazing What You Can Learn From A Tube Of Spit" ) it's time to talk about the tests I've done.

A couple years ago I took the mtDNA test with Family Tree DNA. This is a super simple cheek swab that comes in the mail.  You rub it on the inside of your cheek and mail it back. I only did the basic test at the time (HVR1) due to the cost (on a side note this test is said to be available for $39 starting Spring 2013, that's down from $99).  Even with the basic test I was able to learn my basic Haplogroup and be connected to distant cousins who share my mtDNA.

Confused?  If you look at the diagram below you'll see two types of DNA.   The one on the left is Nuclear DNA.  This DNA is inherited from all of your ancestors and is basically genetic material being passed down from generation to generation.  Most of your genetic material is this type.  This DNA is tested with the autosomal test which will be discussed in my next post.

The diagram on the right shows how Mitochondrial DNA is inherited from a single female lineage.  This makes up less than .001% of your genetic material.  That's not much.  The cool thing about mtDNA is that it has been passed down from mother to child for thousands of years with only minor variations or mutations here and there.  Check out the chart below for the visual.

From http://evolution.berkeley.edu/evolibrary/news/071101_genealogy

While nuclear DNA is mixed over and over with each generation with some genetic material being passed down to one child and slightly different genetic material being passed down to another, mitochondrial DNA (mtDNA) is a direct link to your ancestors thousands of years ago.  Maybe that's nerdy but I think its pretty cool.

By tracing these maternal lines they have broken most of human kind into several basic Haplogroups.  The majority of Europeans belong to one of seven Haplogroups.  A Haplogroup is your "Deep Ancestry." Sharing a common Haplogroup won't tell you if you are related to someone (maybe thousands of years ago but it won't keep you from marrying in most states) but it will tell you where your direct maternal ancestor lived thousands of years ago and their basic migration pattern.  

My basic Haplogroup is J or Jasmine as she has been nicknamed by Dr Bryan Sykes (he writes really good books about this stuff if you find it interesting). 

From Wikipedia:

"Haplogroup J (along with 'T') is associated with the peoples who migrated to Europe and developed farming and herding during the Neolithic Era (8,000 - 10,000 yrs ago)."

The test also breaks down probable heritage of your maternal line by comparing it to where the highest consecrations of people that share your Haplogroup live.  Here is my breakdown:

What this tells me is that my maternal line is 89.16% Western European and 9.38% Middle Eastern.  Kinda cool.  As I said earlier, this is a very small portion of your DNA so these results are from less than .001% of your genetic material but the fact that this has been passed down to me for thousands of years is just really interesting.

On a side note, in Dr Bryan Sykes book Saxons, Vikings and Celts: The Genetic Roots of Britain and Ireland he said they believe "Jasmine" came from somewhere in the Middle East.  I wonder if that explains the Middle Eastern ancestry?

I haven't gotten very far back on my mtDNA line but here's what it looks like so far:

Connecting to Cousins

To find cousins with mtDNA you would need to share a direct maternal line.  For example, check out the very crude chart below.  Since mtDNA is passed down from mother to child and only women can pass it down, if my mothers, mothers, mothers, mothers, mother had another daughter, all of her female descendants would share the same mtDNA to pass down to their children.

In the example above my 4th cousin is connected to the same 3rd great-grandmother by their mothers, mothers, mothers, mothers, mothers, mother therefore we will share the same mtDNA.  By comparing my mtDNA to others in the huge databases on sites like Family Tree DNA they can connect me to others who share a common female ancestor.  Since mtDNA is passed down to both male and female children, my 4th cousin can be male or female but since only women can pass down mtDNA the generations between us must all be women.

Men have something similar called Y-DNA which is their paternal line and is passed down from father to son.  Women don't have Y-DNA so this is exclusively a male thing.  This typically follows a surname since it would be his fathers, fathers, fathers, fathers... There are many groups for most surnames online where men can compare their results and discover which ancestor their surname is from.  This is handy when, for example, two people with the surname "Hawkins" arrived in this country at the same place within a short period of time.  Those men may have been related but by comparing Y-DNA men can determine which "Hawkins" ancestor is theirs. Really cool stuff.

It's Pretty Amazing What You Can Learn From A Tube Of Spit

The first thing people think about when they hear "DNA" is blood. Honestly that is what I would have thought about before the popularity of all the genealogy DNA stuff piqued my interest. After doing a little research I was very happy to learn there are no needles involved in the collection of the DNA. I've done two DNA tests with two separate companies to date and one was a cheek swab and the other was a tube full of spit.  It's pretty amazing what you can learn from a tube of spit these days.

Before I go into what I've learned from my tests let me stick a little something from Wikipedia in here to help explain what I'm talking about.

A genealogical DNA test looks at a person's genetic code at specific locations. Results give information about genealogy or personal ancestry. Generally, these tests compare the results of an individual to others from the same lineage or to current and historic ethnic groups. The test results are not meant for medical use. They do not determine specific genetic diseases or disorders.  They are intended only to give genealogical information. 

Types of tests

There are three types of genealogical DNA tests, autosomal (atDNA), mitochondrial DNA (mtDNA), and Y-Chromosome (Y-DNA).  Autosomal tests for all ancestry.  Y-DNA tests a male along his direct paternal line. mtDNA tests a man or woman along their direct maternal line. Any of these tests can be used to some degree for recent genealogy or for ethnic ancestry.

Make sense?  Here's a diagram for those us that are visual learners:

How DNA works. From  http://www.brainpickings.org/index.php/2008/09/29/the-genographic-project/

There are three things to note from this diagram.

1. Genetic material from both parents is passed down to their offspring. (more on this in a minute)
2. mtDNA is passed down from mother to child but never from father to child.
3. Y-DNA is passed from father to sons but not to daughters (girls don't have Y-DNA).  This usually follows a surname.

Genetic Material

Parents pass down genetic material to their children but they don't pass down all of their genetic material. I watched a really good video by Crista Cowan from Ancestry.com that helped explain that concept. She said people believe that a parent will pass down half of their genetic material like in the picture below they would pass down half an orange, half a strawberry, half an apple, etc...  Actually the genetic material is passed down like below where one parent will pass down a strawberry and a watermelon and the other will pass down a lime and a melon. A second child might get an orange and a watermelon from one parent and a lemon and a melon from the other. Two siblings will both get genetic material from the parents but not the exact same genetic material.

From Crista Cowan on Ancestry.com

This is a super crazy basic version of how the genealogical DNA works but hopefully this will help explain things so my future DNA posts will make sense.