Genealogists for hundreds of years have relied on records and pedigrees to trace family lines. More than one has run into a brick wall, discovered an error from a prior researcher, or simply had a gut feeling that something wasn’t adding up. Until recently there was no way to help confirm your paper trails or even those hunches you might have had. Now, with affordable DNA testing, many genealogists are discovering this new tool in their kit. Unfortunately, most are not sure what they should do with it. In this lecture you will learn the basics of genetics, how DNA can help you, and the tests available to you.

1. Genetic Genealogy:
Using DNA as a Tool in Genealogy
Presented by Shannon Combs-Bennett
tntfamilyhistory.blogspot.com
Facebook: TntFamilyHistory | Twitter @tntfamhist
Why should I do this? This is the one question I am frequently asked when people find out I
know a little about DNA testing and genealogy. Frankly, it is a personal decision. Your reasons may be
different from the person sitting next to you, but usually the common thread is you want to know more
about your family and trying to knock down a brick wall.
Genetic genealogy has taken off in the last decade as DNA sequencing and access to testing has
become easier and more affordable. As with all new technical advances it has had its growing pains but
is now a mainstay in the savvy genealogist’s toolbox. As with everything we do in genealogy, DNA testing
is a tool. It will not give you definitive answers to your heritage, but give you clues. Coupled with paper
genealogical research it can help validate possibilities. DNA has led to more than one person validating a
hunch and proving a connection that was only theoretical on paper.
Many people refuse to do DNA testing because they are afraid that insurance companies, the
government, or their employer may be able to use that information against them. In 2008 the US
Government passed the Genetic Information and Non-Discrimination Act (GINA) so that this will not
happen. Right now the only people who have access to your DNA results at the genetic genealogy
testing centers are you and those you give permission to. Your employers and your insurance
companies cannot access this information. For further details you can read about GINA here:
www.genome.gov/10002328.
Genetics, just like genealogy, has its own language. Understanding the words and their meaning
makes a large difference in the amount of information you can get out of your results. Below is a listing
of genetic (and genealogy) terms that you will need to know.
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Allele: specific form of a gene, one of multiple possibilities. In genetic genealogy used as the
reference for a marker.
Chromosomes: structure in the cell where genes are located.
DNA (Deoxyribonucleic acid): a molecule that contains the genetic instructions for living
organisms.
Gene: a unit of heredity in living organisms. One gene may have multiple forms, or alleles,
defined by different DNA sequences.
Genome: the collection of genes in an organism
Haplogroup: genetic population who share a common ancestor on the paternal or maternal line
with similar SNP mutations.
Haplotype: the set of numbers that make up your genetic testing results.
MRCA: Most Recent Common Ancestor, the closest direct line ancestor shared between
descendants.
Locus: physical location of an allele on the chromosome.
Marker: the specific place on a chromosome with two or more forms. The inheritance of it can
be followed through each generation.
Phylo-tree: Phylogenetic Tree is the reference diagram that show all the haplogroups.
GENETIC GENEALOGY: USING DNA AS A TOOL IN GENEALOGY
© 2014 SHANNON COMBS-BENNETT

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Proxy: the contact person for the DNA test if not the person taking the test.
SNP: Single Nucleotide Polymorphism, a small amount of DNA tested which confirms your
haplogroup by identifying if it has mutated from the ancestral state.
STR: Short Tandem Repeat, the number of repeats of a base pair sequence which then
determines the marker value.
Sub-clade: an offshoot branch of the phylo-tree or a reference to deep clade testing.
There are three main types of DNA tests, with a fourth just making its debut into testing options this
past year. They are Autosomal DNA, yDNA, mtDNA, and now xDNA. You can get a clue as to which part
of the DNA is tested by the word or abbreviation before DNA. Autosomal DNA, also known as admixture
DNA, is the non-sex-determining chromosomes in a person’s cell. yDNA is only for men as it tests the Ychromosome found in males. mtDNA can be taken by anyone and will trace their maternal ancestors.
Finally xDNA tests trace a person’s X-chromosome and can be taken by men and women.
There are quite a few testing companies for a genealogist to choose from. The most used
testing companies are Family Tree DNA (FTDNA), 23and Me (currently not testing), Ancestry DNA
through Ancestry.com, and National Geographic Genographic Project. To help you make an informed
decision on which company can proved the service that you desire Tim Janzen has created a DNA Test
Comparison Chart found at this link: www.isogg.org/wiki/Autosomal_DNA_testing_comparison_chart
Below is a small portion of the resources available to you on this topic. I encourage you to read,
explore, ask questions, and most of all have fun with this new tool in your tool box. It can open doors
for you in your research. All you have to do is take the first step.
Websites
· Genetics Home Reference ghr.nlm.nih.gov/
· DNA Interactive www.dnai.org/
· International Society of Genetic Genealogists (ISOGG) www.isogg.org/
· ISOGG Wiki www.isogg.org/wiki/Wiki_Welcome_Page
· Guild of One Name Studies www.one-name.org/
Blogs
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Your Genetic Genealogist by Cece Moore www.yourgeneticgenealogist.com/
The Genetic Genealogist by Blaine Bettinger www.thegeneticgenealogist.com/13/
DNAeXplained by Roberta Estes dna-explained.com/
On-line Journal of Genetics and Genealogy jgg-online.blogspot.co.uk/
Books
· Terrence Carmichael and Alexander Kuklin. How to DNA Test Our Family Relationships. DNA
Press, 2000
· Colleen Fitzpatrick and Andrew Yeiser. DNA and Genealogy. Rice Book Press, 2005
· George Redmonds, Turi King and David Hey. Surnames, DNA and Family History
· Megan Smolenyak and Ann Turner. Trace Your Roots with DNA: Using Genetic Tests to Explore
Your Family Tree. Rodale Books, 2004
GENETIC GENEALOGY: USING DNA AS A TOOL IN GENEALOGY
© 2014 SHANNON COMBS-BENNETT