DNA / Genetics
The use of DNA testing is a complement to traditional genealogical research. Since about 90 percent of all people who ever lived in this world did not leave a traditional genealogical record, DNA is an opportunity to learn about these ancestors, as well as gaining additional information about the other 10 percent for whom there is a more traditional genealogical record.
DNA is used to learn if participants have common origins; confirm or uncover connections paper trail can't; solve personal history mysteries, especially parentage; and, save time and effort in future research.
DNA stands for Deoyribonucleic acid, a chemical inside the nucleus of all cells that carries the genetic instructions for making living organisms. By analyzing DNA, scientists have gained a powerful new tool for tracing genealogy. Most of our genes get mixed up every generation through sexual reproduction, but some DNA escapes this reshuffling, providing an unbroken record of ancestry.
Chromosomes, the paired threadlike packages of long segments of DNA, are contained within the nucleus of each cell. In humans there are 23 pairs of of chromosomes. In 22 of the pairs both members are essentially identical, one deriving from the individual's mother and one deriving from individual's father. The 23rd pair is different. In females, the 23rd pair has two like chromosomes called "X." In males the 23rd pair comprises one "X" and one "Y," two very dissimilar chromosomes. It is these chromosomes that determine gender.
The Y chromosome gets passed down intact from father to son. The mother's DNA, or the mitochrondrial DNA, doesn't combine with the rest of the genome, so it is inherited unchanged from mother to child. Sons inherit their father's Y chromosome and pass it on to their sons. Sons inherit their mom's mitochondrial DNA but don't pass them on. Daughters pass on their mother's mitochrondrial DNA to their female descendants, offering an equivalent of the Y chromosome for tracing matrilineal descent. Over time as humans have evolved, there have been Y chromosome and mitochondrial mutations for certain groups, and by comparing these mutations, scientists can construct a human genetic tree, revealing how different groups relate to one another.
Based on a DNA sampling from the inside of your cheeks, a testing company can examine your DNA under its microscope, map your markers into your own genetic pattern called a haplotype, then tell you which haplogroup or major branch of the human tree you hail from. For example, haplogroup R1b is Western Europe and J2 is Middle East. Armed with haploytypes, which function as genetic blueprints, genealogists can now join Surname Projects on the Internet.
Mitochondrial test results are reported as a maternal haplogroup (the maternal branch of the world's family tree -- e.g., H, X, J, etc.). Details are presented as a variation from the standard known as the Cambridge Reference Sequence (CRS).
Most projects use Y chromosome testing, and almost all vendors offer Y-DNA tests, but they offer them at varying resolutions. Testing is currently available in three tiers from vendors: 10-15 markers, 23-26 markers, and 37-67 markers. The more markers typically results in greater accuracy. The lower resolutions sometimes can produce false positives.
Single Nucleotide Polymorphism (SNP) is a type of Y-chromosome mutation that occurs so rarely as to be considered a unique event. Once a SNP occurs in a given man (the "founder"), his direct line male descendants carry this genetic signature. Over time, SNPs spread as carriers migrate. By studying concentrations of various SNPs in populations around the world, it's possible to construct a picture of man's migration.
DNA Information Resources
Devine, Donn. "Sorting Relationships among
Families with the Same Surname: An Irish-American DNA Study."
NGS Quarterly 93, 4 (December 2005): 283-293.
Collection Method is a good overview for participants in a
DNA project from Dave Dorsey.
DNA Genealogy Timeline. Compiled by Georgia K. Bopp.
Websites. A listing of links to sites defining genetic
Glossary. Genetic genealogy terms and definitions compiled
and designed to be as simple and easy to understand as possible.
Fox, Robin. Kinship and Marriage: An Anthropological
Perspective. [Harmondsworth]: Penguin, 1974.
Frudakis, Torry N. "Powerful but Requiring
Caution: Genetic Tests of Ancestral Origins." NGS Quarterly
93, 4 (December 2005): 260-268.
GENEALOGY-DNA Mailing List.
Genealogy Library -- DNA/Genetic Genealogy. Articles on
genetic genealogy on Honoring our Ancestors site.
Genetealogy.com -- Genealogy and Genetics. Using DNA testing
to learn more about your roots.
Horowitz, Lois. Dozens of Cousins: Blue Genes, Horse Thieves,
and Other Relative Surprises in Your Family Tree. Berkeley:
Ten Speed Press, 1999.
Society of Genetic Genealogy. Its mission is to educate
others about the use of genetics in genealogy. The society is
non-commercial and non-profit, and offers workshops, speaker's
bureau, forums, and messages.
Kerchner, Charles F. Jr. Genetic Genealogy
DNA Testing Dictionary. Emmaus, Pennsylvania: C.F. Kerchner
& Associates, Inc., 2004. Definitions of words, terms, acronyms,
abbreviations, and pronunciation guide for esoteric words used
in the nascent field of genetic genealogy DNA testing to aid
traditional genealogical research.
Lustenberger, Anita A. "David Meriwether:
Descendant of Nicholas Meriwether? A DNA Study. NGS Quarterly
93, 4 (December 2005): 269-282.
Morse, Stephen P. "Genetic Genealogy Revisited: More Questions
You May Have Been Afraid to Ask..." Association of
Professional Genealogists Quarterly 25. 4 (September 2010):
135-142. Case studies.
Perego, Ugo A., Ann Turner, Jayne E. Ekins, and
Scott R. Woodward. "The Science of Molecular Genealogy." NGS
Quarterly 93, 4 (December 2005): 245-259.
RootsWeb: Genealogy-DNA-L Archives.
Shawker, Thomas H. "Genetic Genealogy: Issues
and Considerations." NGS Quarterly 93, 4 (December 2005):
Shawker, Thomas H. Unlocking Your Genetic
History: A Step-by-Step Guide to Discovering Your Family's
Medical and Genetic Heritage. (National
Genealogical Society Guide, 6) Nashville, Tennessee:
Rutledge Hill Press, 2004.
Shoumatoff, Alex. The Mountain of Names: A History of the
Human Family. New York: Simon and Schuster, 1985.
Smolenyak, Megan Smolenyak and Ann Turner.
Trace Your Roots with DNA Using Genetic Tests to Explore Your
Family Tree. Rodale, 2005. Explain what is and isn't
possible with genetic testing.
Sykes, Bryan. The Seven Daughters of Eve.
W.W. Norton Co., 2002. His premise is that 90 percent of
modern Europeans are descendents of just seven women who lived
45,000 to 10,000 years ago. Brief biographies serve to place
these "seven daughters" into historical context as understood by
Using DNA to
Find Ancestors. From the Wade surname DNA project. Some
basic information about DNA testing.
- Wells, Spencer. The Journey of Man: A Genetic Odyssey. Princeton University Press, 2002. Wells tells us that we can trace our origins back to a single Adam and Eve, but that Eve came first by some 80,000 years. We hear how the male Y-chromosome has been used to trace the spread of humanity from Africa into Eurasia, why differing racial types emerged when mountain ranges split population groups, and that the San Bushmen of the Kalahari have some of the oldest genetic markers in the world. We learn, finally with absolute certainty, that Neanderthals are not our ancestors and that the entire genetic diversity of Native Americans can be accounted for by just ten individuals.
23andMe.com : Learn from your
DNA. With a simple saliva sample we'll help you gain
insight into your traits, from baldness to muscle performance.
Discover risk factors for 94 diseases. Know your predicted
response to drugs, from blood thinners to coffee. And uncover
your ancestral origins.
African Ancestry. Matrilineal and patrilineal tests for
descent from specific countries of Africa and/or ethnic groups,
using a database weighted toward the parts of the continent
where slave traders operated. The African Lineage Database:
11,747 paternal and 13,690 maternal lineages from 160+ African
populations against which to compare results. The results can
link one to a country or tribe, but 30% of paternal lines are
AncestryByDNA. Determines genetic heritage among the four
anthropological groups: Native American, East Asian, sub-Saharan
Africa, and Indo-European.
Laboratories. Paternity, relationship, ancestry,
immigration, forensic, and infidelity DNA testing.
Crucial Genetics. Paternity testing.
Heritage. Genetic genealogy.
Genomics - Native American -- examines main body of DNA and
gives percentage of ethnicity.
EthnoAncestry. Offer unique Y-STR and Y-SNP tests not
available anywhere else.
FamilyTreeDNA. Provides DNA testing for genealogists. But it
is not just a testing service, it also assists with genealogical
research, including surname searches, and offers a "time
predictor" for the likely date of the most recent common
ancestor of two related individuals. Includes family migration
and Native American territory maps.
- Tests for DNA Paternity.
Genetic Genealogy allows us to trace the path of our ancestors
and find out who they were, where they lived and how they have
migrated throughout the world. Order a participation kit and
begin a journey of discover to trace your deep ancestral origins
and pursue the origins of your surname. Login to your control
panel to use Genebase tools and view the progress of your
projects, conduct your own searches, and generate professional
Genographic Project - National Geographic and IBM, with
support from the Waitt Family Foundation, are undertaking the
Genographic Project, a globe-spanning effort to collect over
100,000 DNA samples representing a worldwide range of human
diversity. Led by geneticist and anthropologist Dr.
Spencer Wells, it harnesses a worldwide consortium of scientists
and institutions to collect at least 100,000 genetic samples
from indigenous peoples so as to better understand the genetic
and migratory history of the human race. Broad public
participation is encouraged, for it is a genetic journey we all
share. Go to this site to find information on how you can
With thousands of people that have tested their mtDNA with
different companies, MitoSearch.org is offered as a free public
service that allows individuals that have tested with those
companies to make their results available for comparison.
Ancestors. Y-chromosome and mitochondrial searches, with a
specialty in the "tribes of Britain" and the "seven matrilineal
clans" of Europe, based on the research of company founder Bryan
Sykes (of the Clan of Tara).
Relative Genetics. Paternal line analysis (Y Chromosome),
surname studies, maternal line analysis (mtDNA), ancestral
origins, extended family testing, and consulting services.
Real - mtDNA.
The Sorenson Molecular
Genealogy Foundation - Is building a huge database of family
trees and DNA samples in hopes of demonstrating worldwide
biological connections. People have to get a DNA sample and send
in their records. Participants can get information about
long-deceased forebears, but not for anyone born after 1900. The
SMGF claims to be the only major DNA-matching genealogy project
that is nonprofit and aims to test the entire world. The SMGF's
chief financial backer, James Sorenson, and its chief scientist,
microbiologist Scott Woodward, are Mormons, whose church
emphasizes genealogical research. Their goal is to show the
close relationships "shared by the entire human family."
Genetics. A professional forensic and anthropologic
laboratory that offers genealogical services; claims to have the
world's largest Native American DNA database.
Willuweit S, Roewer L, on behalf of the International Forensic Y
Chromosome User Group, Y chromosome haplotype reference database
(YHRD): Update, Forensic Science International: Genetics (2007)
by the Numbers.
genetic cousins worldwide - independently of which testing
service you have used.The database is searchable on 49
In order to allow people that have tested with the different
companies to make their results available for comparison,
Family Tree DNA is
offering Ysearch as a free public service. We have added several
tools that allow you to compare side-by-side different users -
YsearchCompare - as well as generate a
Distance™ Report, and many other features, including the
upload of GEDCOM files.
Family DNA Studies
- Deboeck, Guido. Flemish DNA & Ancestry: History of Three Families over Five Centuries Using Conventional and Genetic Genealogy. Arlington, Virginia: Dokus Publishing, 2007. Traces the Flemish Deboeck family back almost five hundred years. Included are chapters on family occupations, immigration to America, and genetics.