1.You got those big blue eyes from your grandmother, but chances are you inherited less desirable genes as well.We inherit our DNA from our parents, who inherited it from their parents.Since we all possess genes that can cause or contribute to disease, knowing oneâ€™s DNA and family medical history can be a great resource for someone who learns they have a genetic disorder.
2.Full genome sequencing is right around the corner!The X-prize quest for the $1000 genome will lead to efficient and affordable whole-genome sequencing.As commercial companies crop up and compete for customerâ€™s business, leading to even lower prices.
3.Your grandmotherâ€™s DNA contains clues to her ancestry.X-chromosome, mtDNA, and autosomal genealogy tests contain clues to a personâ€™s ancestry, both recent and ancient.
If you’re a regular reader of this blog, then you know that I am a strong proponent of genetic testing for genealogical purposes.I believe that when used correctly genetic testing can serve as a valuable tool in the genealogist’s toolbox.
A recent visitor found my blog with the search term “is genetic genealogy a scam?”When I recreated the search, I discovered that a previous post on this blog is the leading link for this search. The process made me think about the many people who are skeptical or wary of genetic genealogy.As a scientist, I appreciate and encourage healthy skepticism.After all, genetic genealogy has been available for less than a decade, and it has changed considerably since it was first offered.I believe that anyone who forays into the world of genetic genealogy should have a basic understanding of the science and the application of the results.Just reading about genetic genealogy in the media can give one a distorted view of the technology.Along this point, I recommend reading an interesting article by Rebecca Skloot (author of the upcoming book “The Immortal Life of Henrietta Lacks,” which I can’t wait to read).I was referred to that article by a post on her blog (Culture Dish) entitled “The Bogus-ness of DNA Testing for Genealogy Research” in which she reiterates the point that genetic genealogy tests “simply can’t tell you anything definitive about your heredity unless you’re testing your DNA and comparing it to someone else’s to find out if you’re related.”
The Guardian, a newspaper based in England, recently published an article about genetic genealogy entitled â€œThe appliance of science.“Itâ€™s an interesting article that looks at the pros and cons of genetic testing for genealogical purposes.
The journalist quotes Chris Pomery, author of the up-coming book â€œFamily History in the Genes: Trace Your DNA and Grow Your Family Tree.â€
“In specific cases, genetics is a very useful tool, but it is not a panacea,” he says. “We’re not even close to the situation where, if you’re starting to research your family history, you should begin with a DNA test. At Â£100 or so a throw it’s a lot of money, and you can progress your research a long way first for free.”
Yesterday we began to look at an email conversation I had recently with Jasia from The Creative Gene about genetic genealogy.
Jasia began by asking whether she should test both her and her mother’s mtDNA (I advised her no, because they would be the same sequence), and then we talked about testing her father’s mtDNA. Since her father could not be tested directly, Jasia wondered if her brother could provide a sample of her father’s mtDNA. I explained that although her brother could provide a sample of her father’s Y-DNA, she would have to find other sources for her father’s mtDNA, including her father’s sisters or brothers, or the children of her father’s sisters. She responded:
“Fortunately, my dad came from a large family including 6 sisters 4 of which had children. So I have cousins a plenty and can probably find one of them to help me out with a little saliva
This week I had a terrific email conversation with Jasia from The Creative Gene about genetic genealogy.She left a comment on a recent post, Discovering My Maternal Roots, which asked:
â€œIâ€™m a complete neophyte about DNA for genealogy. Iâ€™m wondering if there is any reason to test myself, and my mother. Since the mtDNA seems to trace the maternal lineâ€¦ is it enough to test just one of us or is there something to be learned by testing both of us?â€
This is a great question, one that many people who are new to genetic genealogy ask.Understanding how mtDNA and Y-DNA are inherited is one of the most challenging aspects of genetic genealogy.I always think of them as mirror images; if you chart your family tree, the Y-DNA travels down the far left line (from your fatherâ€™s fatherâ€™s fathersâ€™ fatherâ€¦) while the mtDNA follows the far right line (from your motherâ€™s motherâ€™s motherâ€™s motherâ€¦).Here is my response to her comment: