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Previous Meetings -- April 2006


April 2006 

Megan Smolenyak 

A Layman's Guide to Using DNA to Further Your Research



Real World DNA Testing

Megan Smolenyak Smolenyak

www.honoringourancestors.com and www.genetealogy.com



What is “genetealogy”?

        DNA testing done for the purpose of learning about one’s heritage

        Mostly used for surname studies to determine if people share a common ancestor

        But other types of tests are also available

What kind of tests are available?




        Genographic Project


        Ethnic: African & Native American

        Sorenson Molecular Genealogy Foundation

How are the tests done? http://www.davedorsey.com/dna.html


Who offers these tests?

        The big 3: Family Tree DNA, Relative Genetics, DNA Heritage

        Other players: Oxford Ancestors, DNAPrint Genomics, Trace Genetics, African Ancestry, GeoGene, GenbyGen, Roots for Real, GeneTree

        Newest entrants: Ethnoancestry, DNA Fingerprint, Crucial Genetics, Chromosomal Laboratories

Most popular: Y-chromosome testing

        Passed from father to son through generations

        Line ends when male dies without issue or only has daughters

        Women have to find male proxy for testing

        Objective is usually to find a match


Surname projects:

        Someone launches a project and invites all with that surname to participate

        As results come in, matchmaking game begins

        Participants are gradually divvied into clusters with their Y-DNA mates

 The matchmaking game:

        Results presented in numbers of repeats at particular markers

        When 2 or more people are tested, you look for (almost) identical results

Matchmaking example:


Y-DNA tests available in 3 tiers:

        10-15 markers; 23-26 markers; 37-43 markers

        More markers = greater accuracy; low resolution can produce occasional false positive

Case study: Smolenyaks



Mitochondrial (mtDNA)

        Passed from mothers to sons & daughters, but sons don’t pass it on

        Primarily a deep ancestry test (Seven Daughters of Eve by Bryan Sykes)

        But also useful if you have a rare mtDNA haplotype, for specific genealogical conundrums, and if dealing with degraded remains



        Deep ancestry Y-chromosome test (Journey of Man by Spencer Wells)

        Predictable through standard test, but some take it for confirmation or to learn more

Genographic Project: www.genographic.com


        African: Y & mtDNA versions; Can sometimes link to country or tribe (African Ancestry)

        Native American: Y & mtDNA versions; Potential for disappointment (Trace Genetics and Relative Genetics)

BioGeographical (DNAPrint)

        Presents results in percentages of Indo-European, Sub-Saharan African, Native American and East Asian

        Somewhat shallow test, so potential for disappointment, controversy, and surprises!

Sorenson Molecular Genealogy Foundation

        Aiming to collect 100,000 samples & family trees

        Correlating genetic (Y, mtDNA & autosomal) and genealogical data (dates, places, names prior to 1900)

        Query database by entering results from commercial lab

Perhaps the most important point to remember about all these tests is that . . . most only address certain portions of the family tree!




        GENEALOGY-DNA Mailing List:


        To find existing surname studies: search www.ysearch.org, www.ybase.org, www.smgf.org, and testing company sites, as well as http://www.worldfamilies.net

        International Society of Genetic Genealogy: http://www.isogg.org/

        Trace Your Roots with DNA: Using Genetic Tests to Explore Your Family Tree by Megan Smolenyak Smolenyak and Ann Turner

        Genetic Genealogy Articles: http://honoringourancestors.com/library.html#three and http://www.genetealogy.com 

Tracing the Tribe - The Jewish Genealogy Blog

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