Mitochondrial DNA – My Maternal Line

As you may know, I’m interested in my family history; and, since I’m curious about these things, I’ve been doing DNA testing to help find out more. You may remember my earlier post on the results of my paternal-line yDNA testing. Earlier this year, I paid up for a test of my Mitochondrial DNA. I now finally have the results back, however it’s taken a little time to write up these results, partially because we’re had the Sommerferien (Summer holidays) here in Germany, partially because the testing company fluffed my results but most importantly because it’s all rather difficult and makes my brain hurt thinking about it.

Anyway let’s start at the beginning

What is Mitochondrial DNA ?

Mitochondiral DNA (hereafter mtDNA) is the DNA you have in your mitochondria, which are quite often described as the power packs of your cells. As a structure, it’s many times simpler than the DNA molecule used to provide the genetic details for your development and function. It has, according to Wikipedia a “circular, covalently closed, double-stranded structure” and contains around 16,569 base pairs, give or take, split into three regions. These region are referred to as HVR1 (Hyper-variable Region 1 – around 500 base pairs), HVR2 (Hyper-variable Region 2, (another 500 base pairs) and the Coding Region – (i.e. the rest, another 15,500ish base pairs). If you want to know more then Google is your friend.

Why is it important to genealogists ?

The good news for genealogists is that mtDNA is only inherited from your Maternal line (i.e. from your mother, who inherited it from her mother ad infinitum). In addition, because it’s fairly small it’s more robust than your other DNA and can be useful in testing archaeological finds. In fact it was mtDNA testing that was used to confirm the identity of Richard the III’s remains found under a car-park in Leicester. The results can determine both your “ancestoral” maternal line (i.e. your deep ancestry from long ago, defined by your Haplogroup) as well as those people who share a maternal ancestor in genealogical times – the last 500 or so years).

My Maternal Line

The maternal line always feels a little stranger than with your paternal line. It’s much easier for me to identify with a string of men carrying the same name father to son. The maternal line is the opposite, each generation is carrying the name of thier father, not the person who gave them their mtDNA. In my case I can trace my maternal line back to a Frances Wetherall, mother of Elizabeth Singleton. Elizabeth was born and baptized in 1797 in Aycliffe village, County Durham. From this record we assume that Frances was originally from Croft-on-Tess, just over the “border” in Yorkshire. Looking at other family records it would appear that Frances’ husband was a weaver, a common occupation for those living in and around Darlington. I believe Frances died in Darlington in 1829, aged 72, which puts her birth around 1755. Below is a screen-grab of Elizabeth’s baptism record. The records are available through the good folks at familysearch.org, as explained in this post.

Elizabeth Singleton, born: Aug 6 1797, baptized Dec 28 1797, child 1st Daughter of John Singleton, of the Parish of Haughton, native of the Parish of Gainford, by his wife Frances, late Wetherall, native of the Parish of Croft.

My Result – Big Picture stuff

My mtDNA is part of a Haplogroup I2. Which shows my maternal lineage to be broadly European (duh !), although it’s origin is believed to be in Western Asia, and is found in populations across western Asia and Europe. The highest percentages of Haplogroup I (according to the Genographic Project) are in Pakistan (8.7%) and Denmark (6%), with smaller percentages (between 1% and 4%) scattered across Europe. The Genographic Project itself has identified only 0.4% of all it’s samples as being Haplogroup I2.

My Results – In details

Within the Haplogroup I, I am categorised more precisely, based on the following mutations within my mtDNA:

• I2’3 (this category means both I2 and I3 subclades) since I have both T152G and G207A. These codes show the position and type of mutation from the Revised Cambridge Reference Sequence. Again it’s something you will want more eloquently explained by Google than me.
• I2 due to A15758G.

After that it all goes rather pear-shaped. It turns out I carry a number of rare, probably un-reported mutations, most specifically C16259g. In one of the research projects for my Haplogroup I am the only carrier of this mutation. As a result the project administrator encouraged me to submit my results to Genbank (a database of DNA results used by research scientists). The net result is that I could one day have my own “subclade” with the Haplogroup I. The other consequence of this is that, frustratingly,  I have no significant maternal matches within the database of my testing company.

The end result is I both pleased and disappointed. I’m rather happy to have the opportunity to have the mtDNA of Frances Wetherall recorded for science, even if I’ve yet to trace anyone closely related to her. Naturally I don’t pass on my mtDNA to my kids, but I’m reasonably confident, from my other genealogical research, that there is a maternal line  out there somewhere that will continue to pass on Frances’ mtDNA.