January 29, 2015

Learning About Genetic Genealogy, Part 1

Earlier this month, I spent an exciting (and exhausting!) week at the Salt Lake Institute of Genealogy (SLIG). My brain is full of new information about genetic genealogy, and my flash drive is full of new records about my ancestors. I enjoyed reconnecting with friends who share my passion for family history, as well as meeting new people.

I took the course “Getting Started in Genetic Genealogy,” coordinated by Debbie Parker Wayne, CG, CGL. Blaine Bettinger, PhD, JD, and CeCe Moore also instructed significant sections. The three of them made a good team, and we covered a lot of ground. The binder of handouts we received will make a great resource going forward.

Many people have asked me what the course was like, and whether I’d recommend it. The answer to the latter is definitely yes. First of all, SLIG is an incredibly well-organized institute, the new hotel facilities are good, and the people couldn’t be nicer. Still, the true test of a course is in its content and instructors, and I’m happy to say this one delivered on both counts.

We started out with an overview of DNA testing and basic genetics, talking about the different tests and the “big three” companies: Family Tree DNA, 23andMe, and AncestryDNA, as well as specialty testers. We spent some time the first day learning some scientific vocabulary. I now understand terms like centiMorgans, alleles, recombination, pseudo-segments, and endogamous populations, not to mention MCRA, CRS, IBD and IBS. Not sure of the difference between a SNP and a STR? Neither was I before this course.

Debbie Parker Wayne covered mitochondrial (mtDNA) testing, and what it can reveal about your direct maternal ancestry far back into history. Crucial to this is understanding that a mother passes her mtDNA to all her children, but only daughters can then pass it on to the next generation.

While using mtDNA to solve genealogical problems for recent generations can be challenging, we talked about ways of approaching it. For one thing, mtDNA can often be used to either support or refute a supposed relationship. It also can be used to prove questions of Native American ancestry through the mother’s line. For me, a key point in our mtDNA discussion was understanding more about haplogroups, which indicate where your maternal ancestors originated many hundreds of years ago.

Y-DNA also deals with deep ancestry, but on the opposite side of the pedigree chart. Only males inherit a Y chromosome, so Y-DNA passes from father to son through many generations, with occasional small changes. These changes, or mutations, can provide big clues for families. Blaine Bettinger presented an excellent discussion of the advantages and limitations of Y testing, using Y-DNA results, finding Y-DNA cousins, surname projects, STR markers, haplotypes and haplogroups. He told us about some third-party databases and tools for analyzing results, and showed how Y-DNA can be used to identify whether two males share a common paternal ancestor.

We also learned about X-DNA, which is tied to the sex chromosomes. A female inherits one X chromosome from her mother and one from her father. A male inherits an X chromosome from his mother but none from his father (he gets a Y instead). Because of its more complicated inheritance pattern and the fact that it hasn’t been studied as much, X-DNA often gets overlooked. In the right situations, though, it can be used to narrow down the ancestral lines you should focus on.

In addition to lectures, we did in-class projects designed to identify individuals on a pedigree chart who could be tested for a common ancestor. One takeaway from this was that when you start to work with DNA, those collateral relatives—your grandfather’s brother’s kids, your grandmother’s aunt’s kids, and cousins of every stripe—become vitally important. I have a renewed sense of how valuable it is to include these collaterals in my traditional genealogical research.

That's a quick overview of our first two days. I'll talk about what we covered the rest of the week in my next post, and tell you about opportunities to take a similar course at GRIP and SLIG. There was just too much happening to fit it all into one!


DNA image: "DNA methylation" by Christoph Bock (Max Planck Institute for Informatics) - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:DNA_methylation.jpg#mediaviewer/File:DNA_methylation.jpg


  1. Your explanation of mtDNA made me think of the old (probably not true?) story that male pattern baldness comes solely from the mother's side. And x-DNA does not get studied as much? Hope that is changing, with all the women scientists we should have by now. Kudos on your work! You've taken a long-time interest and become an expert who shares her knowledge.

    1. Carrie, my husband may not appreciate it if I look into male pattern baldness too much :). But it is interesting to see how chromosomes get passed down, and what they may be able to tell us about people we never had the chance to meet. Thanks for reading and your kind words!

  2. How wonderful that you got the opportunity to go to SLIG, Shelley! It sounds like a worthwhile experience. Looking forward to part two...

    1. Thanks, Jacqi , it really was worthwhile. I'm working on part 2 now. Hope to be able to see you again at a conference or institute in the future.


Thank you for reading my blog! I welcome and appreciate your comments.


Related Posts Plugin for WordPress, Blogger...