I originally did y-DNA testing with FTDNA as part of establishing my Velten Surname Project. Since then my wife and I took advantage of 23andme's 2010 year-end promotion that offered their complete test series for only $99. The 23andme results included both health-based and genealogy results. I have ignored the health-based results for the most part, other than to note that my wife indeed has the gene for bitter taste, explaining her dislike for those wonderfully healthful vegetables, broccoli and Brussels sprouts. Other than that, the value of genetic testing for health outcomes seems limited and controversial (see my blog article on this). Below I will provide:
- A quick overview of DNA testing for genealogy
- Some of the genealogical results we have derived from DNA testing
- A set of resources for testing and for comparing and sharing results
Quick Overview of DNA Testing
Human DNA consists of 46 chromosomes in two strands, 23 in each. Two of the chromosomes are the sex chromosomes, X and Y. The female's egg always contributes an X chromosome. The sperm determines the sex of the embryo depending on whether it contains an X or Y sex chromosome. Males have an X (from the mother) and a Y (from the father). Females have two X chromosomes, one from each parent. The Y chromosome is passed from father to son and that is why y-DNA can be used to trace a surname line. That is why y-DNA tests were among the first available to genealogists.
The other 22 chromosomes are called the autosomal chromosomes and we get one from each parent. The autosomal chromosomes allow us to find relationships between many ancestors without following a direct line. 23andme and FTDNA have recently introduced tests for autosomal DNA.
Finally, there is a third kind of human DNA unrelated to nuclear DNA (the DNA in the nucleus of the cell). This is mitochondrial DNA, the DNA contained in the mitochondria located in the cell outside of the nucleus. Mitochondria are structures located in the cell that produce chemicals used to power cell functions. One theory is that mitochondria are bacteria or another organism trapped by the cell long ago and adapted to be chemical factories. They have their own DNA structure which is passed only by the mother to the embryo (the sperm's single mitochondria being located in the tail which doesn't make it into the egg). Everyone gets their Mitochondrial DNA from their mothers but only women can pass it to their children. Mitochondrial DNA (mt-DNA) allows us to trace the maternal line, regardless of surname.
Humans share 99.5% of their DNA with each other. The variation we see comes from locations on the chromosomes called Single Nucleotide Polymorphisms or SNPs, pronounced "snips". When a cell splits, it must copy the nuclear DNA and rarely mutations will occur. Sometimes the mutations have no effect, sometimes they change the expression of a gene, and sometimes they cause disease.
Each individual has a unique chromosomal expression that can be analyzed to identify that individual. We can also compare the chromosomal expression of two individuals to determine how closely they are related and to estimate how long ago they shared a common ancestor. Genetic genealogists pick certain SNPs known to frequently mutate out of the 10 million SNPs in the human genome. They look for combinations of SNPs that tend to be transmitted as a unit, called haplotypes. Population geneticists have organized groups of similar haplotypes into haplogroups believed to have a common ancestor. Most studied are the y-DNA and mt-DNA haplogroups. In the following sections, I will relate what Martha and I found out about our haplogroups.
Test results from 23andme shows my paternal haplogroup is R1b1b2a1a1, supposedly a group concentrated around the fringes of the North Sea (aka Germany). R1b1b2 is the most common haplogroup in Europe, having originated around 17,000 years ago and spreading from SW Asia into Europe. Because I did my original testing on FTDNA and I host my Velten Surname Project there, I have more extensive results from the Deep Clade testing I have done at FTDNA.
FTDNA also uses a different nomenclature from 23andme. FTDNA tests show my confirmed paternal haplogroup to be R1b1a2a1a1a4. From Deep Clade testing I know I am U106+, Z336+, Z326+, L48+ and null 425. The U106 project hosted at FTDNA is studying the U106 branch of the R1b tree and most contributors have roots in Northwest Europe and the British Isles, which matches what I know about the Veltens. I am guessing that Jacob Veldin came from Alsace, where a large number of Veltens are concentrated, but he could also have come from Luxembourg or Belgium.
My mt-DNA results came from 23andme and are somewhat interesting. The haplogroup is X2b which, while fairly rare (just 2% of European population), is one of the most widespread haplogroups, occurring almost everywhere. It is believed to have originated 45,000 years ago, while it spread rapidly after the glaciers melted about 15,000 years ago. It is spread across Europe in small amounts, but some of the highest concentrations are in Georgia (8%), the Orkney Islands in Scotland (7%), and among the Druze nomad populations in Israel (11%). The X haplogroup was founded by one of the daughters (Xenia) in Bryan Sykes book, The Seven Daughters of Eve.
Using the Davidski calculator on GEDmatch.com, my Dodecad K12b admixture proportions are:
These results seem to indicate I am some mixture of northern European and Meditteranean.
The new Davidski calculator for Eurogenes K36 admixture has these interesting results (null results omitted from table):
|East Central European||9.32%|
Wow, look at those 18.01% Italian and 15.43% Iberian results. The Veltens and Thesses were not blond, blue-eyed Germans. Hair colors were brown or black and eyes brown or hazel. Both came from the Rhineland area of western Germany, so you can imagine us being the result of a mixture of Roman and Germanic tribes.
Martha's mt-DNA haplogroup is T2b. The T haplogroup originated about 45,000 years ago in the Near East and did not spread until after the glaciers melted about 15,000 years ago. T2 was an offshoot that spread along the North African coast into Europe. It is widespread, at low levels, in Scandinavia, Germany, Britain and France. This seems to match her Scotch-Irish/English/Irish background.
The Davidski Eurogenes K36 admixture tool on GEDmatch produces these results for Martha:
|East Central European||8.25%|
Our Pedigrees and Other Resources
To help locate potential matches with distant cousins, I have posted Pedigree charts for Martha and myself below. Doing it here is helpful becuase the charts are linked into the database where complete details, such as I have them, can be viewed. I also include some links to reources for matching and comparing DNA results.
- Dave's Pedigree
- Martha's Pedigree
- Ysearch Ysearch is a site that allows you to post your y-DNA results and look for matches with other posters. It is hosted by Family Tree DNA so exporting from the FTDNA site to Ysearch is automated.In addition you can manually post a GEDCOM of your pedigree. Ysearch also allows posting of test results from other vendors. Search by genetic matches, last name, and haplogroup are supported.
- Gedmatch GEDmatch allows you to upload the raw data file from the FTDNA Family Finder test or the 23andme Relative Finder test. You can also upload a GEDCOM of your pedigree. This allows you to look for matches with other users of GEDmatch based on the autosomal DNA results of these two tests.
- International Society of Genetic Genealogy A good source of reference information and tutorials on genetic genealogy.
- Y-DNA Haplogroup Tree The reference tree of human y-DNA Haplogroups maintained by ISOGG.
- Global human mtDNA phylogenetic tree The reference tree of human mtDNA phylogeny.
- Your Genetic Genealogist Blog A genetic DNA blog by CeCe Moore.
- The Genetic Genealogist Blog A genetic DNA blog by Elaine T. Bettinger.