Endogamous populations are much harder to work with in genetic genealogy because you have double and triple 6th cousins who look like 2nd to 3rd cousins when you compare their DNA to yours. Ashkenazim (see my Ashkenazi DNA post), Mennonites (see Tim Jantzen’s project), and Polynesians (See Kalani Mondoy”s project) are a few of these intermarried groups. See the ISOGG wiki for a further discussion of endogamy.
A fellow genetic genealogist, Israel Pickhotz, has written a fascinating book about how he has confirmed and refuted many genealogical connections in his extended Ashkenazi family. He did this by testing every cousin he could. That story is an inspiration to those of us frustrated by using DNA to research our jewish roots. It is as easy to read as it can be, given that genetic genealogy is not easy to understand. Lara, blogging at her blog Lara’s Family Search, wrote an excellent description of the book in her review which is hard to improve upon.
Israel’s blog continues his story: http://allmyforeparents.blogspot.com/
Another DNA expert, Jim Bartlett has just written an interesting blog post investigating the math of endogamy at his segmentology blog. As it is titled part I, I am looking forward to part II.
The problem comes when so many cousins marry each other as you go back up the tree that it gets difficult to calculate the shared DNA. Plus once you get past 3rd cousins, DNA inheritance becomes more and more random anyway.
On my Norwegian side, my Dad has a woman “MB” listed as a 2nd to 3rd cousin who upon investigation was found to be a fifth cousin three times and a sixth another time. She shares 49 cM over 4 segments with my Dad and a whopping 141 cM in 8 segments with my third cousin in Norway. That third cousin is related the same way to MB as we are, but he, like MB, descends from a cousin marriage within this group.
Richard Hill is a very fine writer. I could not put down the story of his search for his biological parents, Finding Family: My Search for Roots and the Secrets in My DNA, which reads like a mystery novel.
He has put together an e-book, Guide to DNA Testing: How to Identify Ancestors, Confirm Relationships, and Measure Ethnic Ancestry through DNA Testing, available from Amazon, which is a very simple guide to personal DNA testing. Normally $.99, it is free through 12/16.
It will help you choose which test to take and why. It is only about 30 pages. It is not comprehensive but it does answer your basic questions. It is meant for those totally new to DNA testing not for the experienced. Although if you have tested, but still have many questions, they may be answered by this book.
This may also make a nice gift for relatives who are thinking of doing DNA testing.
When I was working on a cousin’s colonial ancestry, googling an ancestor’s name* would often find a book digitized and online at google, for example, a local history of Stamford, CT. Recently I saw a post about the genealogically related books digitized by familysearch which said “There are many thousands of historical and genealogical books available to read online. They are indexed so I was able to find old towns where ancestors lived, genealogies of families …”
In short order I found a book at familysearch.org about Norwegians in Brooklyn that listed my granddad and both sets of my great grandparents who lived there. The details of that are posted here on my family history site.
After I excitedly announced this on one of my favorite mailing lists, others chimed in with more online book resources. So with permission, I am including June Byrne’s list of these and tips on using them.
*n.b. when googling a name, put it in quotes to get an exact match, e.g. “Lawrence J. Munson”
The rest of this post is adapted from a write-up by June C. Byrne.
There is finally a really well-done book on understanding and using autosomal DNA testing, so of course I have been wanting to review it. At last on the plane to Rootstech 2014 I had the time to read it: Genetic Genealogy: The Basics and Beyond by Emily Aulicino. I thought that I would know most of what was in there but was pleasantly surprised by a number of helpful insights.
I will reread chapter 6, “Convincing a Person to Test” several more times. I have found that the DNA match ups of my 2nd cousins who have tested are extremely useful for figuring out which line a new relative is related on. Thus I need advice on how to get few more of them to test!
One lucky reader will get a free pass to Rootstech 2014 this coming February (an educational event for the howtos of using technology in family history research), since I will be an official rootstech blogger. So my idea was to award it to whomever comes up with the best question for me to ask Spencer Wells at the conference. I am expecting to have a private interview with him, video recorded and posted here. So send me your questions via my contact page by January 30th.
It was Well’s book, Deep Ancestry: Inside The Genographic Project, that sparked my interest in population genetics and genetic genealogy. After I read it, I did the original NatGEO DNA test. Then I transferred the results to FamilyTreeDNA.com but my mitrochondrial DNA was too deep in the past to satisfy my genealogy cravings. Soon thereafter I heard about 23andme and tested there. Twisted the arms of many family members and relatives to get tested, including my father, whom I had tested by both of those sites. In the process I read lots of books and blogs. The marriage of genes and genealogy known as genetic genealogy had me firmly hooked.
Read on for more about all the things I have enjoyed reading to expand my understanding, n.b. favorite blogs are in the column on the right towards the bottom. Continue reading