Last week I wrote about the results of my Family Finder autosomal DNA test by Family Tree DNA (see “A Review of Family Tree DNA’s Family Finder – Part I“). The Family Finder test uses a whole-genome SNP scan to find stretches of DNA shared by two individuals, thus identifying your genetic cousins (and will soon include the Population Finder analysis of admixture percentages). I currently have over 33 genetic cousins in Family Finder, and I’m working with them to identify our common ancestor(s).
The Affymetrix microarray chip used by FTDNA includes over 500,000 pairs of SNPs located on the X chromosome and the autosomes (no Y chromosome SNPs). Via SNPedia:
FamilyTreeDNA uses an Affymetrix Axiom CEU microarray chip with 3,269 SNPs removed (563,800 SNPs reported) for autosomal and X (but not Y or mitochondrial) ancestry testing for $289. Other sources have cited 548011 snps. This platform tests 1871 of the 12442 snps in SNPedia.
Mary Carmichael, a science editor for Newsweek, is in the midst of a week-long dilemma. This Friday, after reading a series of articles written by members of the DTC genetic testing community, she will decide whether she should purchase a genome-wide SNP analysis. Although the decision might be a simple one for some, in light of the recent critique of DTC genetic testing in the media, in the literature, and by the government, it is certainly understandable that Mary is looking for further insight into her decision.
Today, Mary is asking “What Can I Learn From At-Home DNA Tests?” and has gathered answers to her question from a wide variety of writers and scientists, including myself. Since the Newsweek site only has space for a brief introduction to each topic, this post is meant to be a more in-depth answer what Mary could learn about her ancestry from a DTC test.
Since late 2007, several “direct-to-consumer” or “DTC” genetic testing products have entered the marketplace, many of which offered some degree of autosomal ancestry analysis (including 23andMe, deCODEme, and Pathway Genomics, among others).
In early 2010, genetic ancestry testing company Family Tree DNA announced that it would begin offering a new genetic genealogy product (see “Announcing Family Finder – An Autosomal Test From Family Tree DNA”). The new product, called “Family Finder,” is one of only a very few autosomal genetic genealogy tests available to consumers.
The Family Finder test uses an Affymetrix microarray chip that includes over 500,000 pairs of locations called single nucleotide polymorphisms (SNPs) in your autosomal DNA. Once the SNPs are analyzed, FTDNA detects linked blocks of DNA that indicate a common ancestor. The number and size of these linked blocks is used to determine how recently or closely two people are related. From the Family Finder FAQ page:
In honor of mother’s day, I’m reposting a portion of an entry from March 16, 2009 (“Visualizing Your Genetic Genealogy“).Â It also follows a SNGF from Randy at Genea-Musings called “Matrilineal Line.”
In my genealogical research, I have sometimes found myself missing the trees by focusing on the forest.Â I think it happens to many genealogists â€“ we get caught up in the research, the dates, the places, and we forget that there was so much more to people than their vital statistics.
This can happen to genetic genealogists as well.Â The connection between the results of a DNA test and the individuals in our tree can be easy to forget and difficult to visualize.Â Take the results of an mtDNA test, for example.Â The results are obtained from a tiny piece of DNA that has traveled thousands of years (and often thousands of miles) through hundreds of individuals to end up in your cheek cells and on the tip of a swab.Â Everyoneâ€™s mtDNA is the product of an amazingly rich story that has largely been lost to history.
Late last fall, Family Tree Magazine requested nominations for the best genealogy blogs, and then opened voting for the nominated list.Â Yesterday, they announced the winners of the voting.Â Diane Haddad wrote about the announcement on the Genealogy Insider blog, and Maureen Taylor wrote the article that will appear in the May issue of Family Tree Magazine: “Fab Forty.”
I am very pleased and honored to announce that TGG was selected as one of the 40 Best Genealogy Blogs, in the category of genetic genealogy. I would like to thank everyone who nominated and voted for me.Â I have been very fortunate over the last few years to interact with a fascinating array of readers, and I am thankful for every one of them.
When I started blogging in February 2007 (I just recently counted my third anniversary of TGG!), there were very few blogs in the genetic genealogy space.Â Today there are a number of interesting and well-written genetic genealogy blogs.Â See my recent round-up at “10 Great Blogs for Genetic Genealogists.“Â Each of these blogs is well worth adding to your reading list.
In October 2008, I reviewed an article by Dr. Alondra Nelson in the journal Social Studies of Science entitled â€œBio Science: Genetic Genealogy Testing and the Pursuit of African Ancestryâ€ (Social Studies of Science 2008 38: 759-783).Â The article was about the complex interpretation of the results of genetic genealogy testing by African-Americans and black British.Â Dr. Nelson is Associate Professor of Sociology at Columbia University in NY.
On Friday, an article by Dr. Nelson appeared in The Chronicle of Higher Education entitled “Henry Louis Gates’s Extended Family,” which is an introduction and review of the current PBS documentary miniseries Faces of America. Regarding the genetic testing aspect of the show, Nelson writes:
The Social Security Death Index (SSDI) is a searchable database created from the U.S. Social Security Administration’s Death Master File, which contains the name and social security number of deceased persons reported to the Social Security Administration since roughly 1962.Â In addition to being used by genealogists, the Death Master File and SSDI are used by financial firms and government agencies for various reasons such as preventing identity fraud.
A Genealogy Meme Using the SSDI
Michael Neill at RootDig has two posts â€“ â€œHave You Searched for All Your Ancestors in the SSDI?â€ and â€œMy in-laws in the SSDIâ€ â€“ that list his and his wifeâ€™s ancestors in the SSDI.Â Michael has 7 ancestors, while his wife has 6.
The Evansville Courier & Press has a great article â€“ â€œAt 97, life is worth a big fuss: Six generations gathered at matriach’s birthday partyâ€ â€“ which contains a picture of six generations of the Moore Family of Indiana.Â The picture shows a newborn and 5 generations of her ancestors; her mother, grandmother, great-grandmother, great-great-grandfather, and great-great-great-grandmother!Â It is truly amazing and I highly recommend clicking over to the article to see it.
My Mother’s Mother’s Mother’s Father’s Mother (whew!)
The picture led me to wonder who was my motherâ€™s motherâ€™s motherâ€™s fatherâ€™s mother (following the same lineage in the articleâ€™s picture), and whether I ever met her.Â After consulting my family tree software (maybe I could have done it from memory, but I thought Iâ€™d save some time!), I discovered that her name was Jemima Cooper.Â I never had the opportunity to meet Jemima because she died 53 years before my birth.Â She would be 118 years old today.
An article in the United Arab Emirate newspaper The National (wikipedia) does a terrific job of highlighting recent research from Family Tree DNA.Â The story – â€œDNA could illuminate Islamâ€™s lineageâ€ â€“ discusses research that has attempted to elucidate the Y-DNA signature of Mohammed.Â Although Mohammed did not have a son, he had a daughter who married her paternal second cousin, thus passing to Mohammedâ€™s grandchildren the same Y-DNA.Â From the article:
â€œFor almost 1,600 years, the title Sharif, Sayyed, or Habib has been bestowed on Muslims who have been able to trace their roots back to the Prophet Mohammed through intricate family trees, oral histories and genealogical records. But now an American DNA lab says it may have identified the DNA signature of descendants of the Prophet Mohammed, and perhaps the prospect of a direct, more accurate means of confirming or identifying such a connection.â€
This has been a great week for The Genetic Genealogist, and I just wanted to send out my gratitude.
First, TGG was included by Chris Dunham of The Genealogue in his list â€œ10 Genealogy Blogs Worth Readingâ€ at Blogs.com!Â Iâ€™m truly honored to be listed among the other great bloggers in the article.Â (Like Chris, I was recently asked to create a Top 10 list which I believe will be posted soon, but my list focuses more on genetic genealogy and personal genomics blogs).
And second, TGG was listed as #9 on the ProGenealogists list of The Top 25 Genealogy Blogs of 2009!Â The rankings were based on â€œoverall content, Technorati rating, and industry experience.â€Â It is an honor to be included among this group of incredible bloggers.Â Be sure to visit the website to check out the other blogs on the list.