If you’ve researched (or need to research!) in New York, if you’re interested in DNA, or really if you’re interested in genealogy in general, won’t want to miss the 2015 New York State Family History Conference being held in Syracuse, New York on September 17-19, 2015!
This year’s cruise is focused on using the newest tool for your genealogical research, DNA testing. Are you a DNA newbie? No problem, with more than 20 different genetic genealogy presentations, this conference will take you all the way from complete novice to an intermediate user ready to add DNA to your genealogy toolbox. Are you well-versed in genetic genealogy? Come and learn the latest tips and tricks to enhance your DNA knowledge.
In addition to a full slate of presentations, one-on-one consultations, and several group sessions, conference attendees and passengers will have plenty of time to enjoy the sights, sounds, and flavors of the Caribbean as the Coral Princess makes stops in the topical destinations of Aruba, Cartagena, Grand Cayman, and even makes a partial transit of the unparalleled Panama Canal. You can find the full schedule for this amazing trip here.
I’ve recently noted a trend among genealogists to discount unexpected (or unwanted?) DNA test results in order to make the results fit an existing hypothesis, instead of properly re-evaluating the hypothesis in light of the new DNA evidence. (This is NOT made in reference to any specific person, post, or question; it is rather something I’ve been mulling over for some time).
Let’s take third cousins as an example. According to Family Tree DNA’s FAQ, you will share detectable DNA with approximately 90% of your third cousins under FTDNA’s threshold. According to AncestryDNA’s help page (see “Should other family members get tested?”), you will share detectable DNA with 98% of your third cousins under AncestryDNA’s threshold. In other words, if you have 100 third cousins and they all get tested (how’d you do that?), you will share DNA with 98 of them.
As you might recall, a few weeks ago I sent out a call for information about the amount of DNA shared by people having a known genealogical relationship. I was hoping to get a better picture of the ranges of the amount of DNA shared by people in these relationships (through about the third cousin range). Although people like Tim Janzen have gathered this type of data and so kindly made it available for everyone, I felt like more data was needed.
What is the range of cMs shared by third cousins? What does the distribution within that range look like? Does the longest segment factor into that at all? If so, how?
These are the types of questions I wanted to examine. And to entice submissions, I offered a free Family Finder kit to one lucky person that submitted data prior to April 1, 2015.
The following is a guest post by Ann Turner, founder of the of the GENEALOGY-DNA mailing list at RootsWeb and co-author (with Megan Smolenyak) of “Trace Your Roots with DNA: Using Genetic Tests to Explore Your Family Tree.” Thank you Ann for this terrific post!
Genetic genealogists use autosomal DNA testing to locate people who share some DNA, enough to point to a relationship in a genealogical time frame. We’re not impressed by accidental matches that occur simply because all humans share 99.9% of their DNA. We want to be confident that the shared DNA segment is Identical by Descent (IBD) from a particular common ancestor, one who lived some number of generations in the past.
Two practical difficulties stand in the way of definitive confirmation. One is that our pedigrees are not complete, and we cannot test every link in the chain to prove that the segment traveled down the pathway we’ve identified through the paper trail. Indeed, as more data accumulates we frequently discover that a match we attributed to one ancestor must have come through an entirely different line.
[Read on to learn how you could win THREE hours of FREE consultation and research from me for registering in this course before March 21st!]
For the next two Saturdays, March 21st and 28th, I will be spending some quality time with genetic genealogists! My new course entitled “(Finally!) Understanding Autosomal DNA” is a four session course designed to educate genealogists on all the ins and outs of autosomal DNA.
The course is being offered through the wonderful new Virtual Institute of Genealogical Research. The Virtual Institute offers courses on a wide variety of genealogical subjects, providing vigorous year-round education for the genealogical community using a virtual platform.
The four courses will provide attendees with the fundamentals of autosomal DNA, third-party tools, and triangulation. Here is the course schedule (all times U.S. Eastern):
21 March 2015
11:00am – “Introduction to Autosomal DNA”: Learn the fundamentals of autosomal DNA and compare company offerings.
1:00pm – “Using Third-Party Tools”: Free tools offer powerful additional analysis of autosomal DNA test results.
EDIT (3/31/2015) – Beginning on April 1, 2015, I will no longer be able to accept submissions other than through the portal. My sincerest apologies, and I so greatly appreciate the files that have been submitted this way, but I have been inundated and won’t be able to take the extra time to process any non-portal submissions made after April 1, 2015. Thank you!
I need your help! I’m trying to gather data about the ranges of DNA shared by known relatives. How much DNA do you share with your sister? your brother? your second cousin? While it is possible to predict approximately how much DNA you share with a close relative, the actual numbers vary more than you might think.
If you’re interested in participating in this project, I’m looking for two numbers for the known relationship: (1) the total amount of shared DNA in cMs; and (2) the largest shared block in cMs. At Family Tree DNA, for example, you can find the numbers here:
With a database of over 700,000 genotyped members, AncestryDNA has generated over one billion cousin connections to date. In 2015, we project this database to grow to exceed well over one million genotyped members, resulting in even more and higher quality cousin matches.
Following the successful launch of AncestryDNA in the UK, we will soon be bringing the service to our members in Australia and Canada, and in doing so, will connect the major English-speaking migrations and globally connect families like never before.
Building on DNA Circles, in 2015 we will launch a new experience that will use the latest genetic technology to discover new ancestors without the customer having to search records or build a family tree. This new feature will transform how family history research is done by providing valuable hints to help experienced genealogist looking to break through brick walls, as well as open family history to a whole new segment of the population. Through this new experience, AncestryDNA customers will be able to discover new ancestors as far back as the 1700’s by connecting into existing DNA Circles.
DNA Circles Without Family Trees
On the last point, in the coming weeks AncestryDNA will launch an extension of the DNA Circles tool in which they assign you to a DNA Circle without having a family tree connection.
Currently, you must have a decent public tree in order to be put into a DNA Circle based on genealogical relationships. Using this new tool, however, you will (potentially) be put into circles without a tree showing that you belong to the circle (in other words, based only on genetic relationships regardless of the trees).
Many genetic genealogists, myself included, often talk about DNA segments getting “broken up” or “broken down” as they are passed from one generation to the next. But this language can be misleading, since DNA isn’t really “broken up” into pieces when it passed down; instead, a few pieces are traded between nonsister chromosomes in a process called RECOMBINATION.
Genetic recombination is a process of crossover between chromosomes during MEIOSIS (meiosis = a very specialized cell division that creates eggs and sperm for reproduction). Very early in meiosis, the cells duplicate the chromosomes. Normally, every cell has 23 pairs of chromosomes, for a total of 46 chromosomes. However, in the first step of meiosis, the chromosomes are duplicated to result in a total of 92 chromosomes. There are 4 copies of chromosome 1 (2 copies of the chromosome you got from your mother, and 2 copies of the chromosome you got from your father). There are 4 copies of chromosome 2, and so on.
There will be lots more to come, including guidelines for Y-DNA and mtDNA testing and interpretation, as well as some guidance for citing DNA test results in reports, scholarship, and in general. Stay Tuned!