The basics of DNA testing for genealogists

By Kitty Munson Cooper
Blogging at blog.kittycooper.com

98% shared
DNA with him
99.7% with me

are NOT the same as
personal genome tests

Forensic DNA tests

23 pairs of chromosomes

Image of painted (SKY) chromosomes - Courtesy of DeWitt Stetten, Jr., Museum of Medical Research

Three types of personal DNA tests

Y test for father's father's line

mtDNA for mother's mother's line

Autosomal DNA test for all your ancestors

Diagrams from the NIH http://ghr.nlm.nih.gov

SNP - Single Nucleotide Polymorphism

a DNA mutation where a single letter chang3s

STRs are short tandem repeats

An extra copy is made of a sequence of DNA

An extra copy is made of a sequence of DNA

An extra copy is made of a sequence of DNA

An extra copy is made of a sequence of DNA

An extra copy is made of a sequence of DNA

2 Types of Y DNA Tests

Deep ancestry - haplogroup

More recent ancestry - surname studies

Y Haplogroups

By Chakazul, via Wikimedia Commons [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

Y Haplogroups

By Chakazul, via Wikimedia Commons [GFDL (http://www.gnu.org/copyleft/fdl.html)

Mitochondria under the microscope

Image Source: Dartmouth EM images, http://remf.dartmouth.edu/imagesindex.html
By User:Maulucioni via Wikimedia Commons [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

Mitochondrial Haplogroups

By User:Maulucioni via Wikimedia Commons [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

Mitochondrial Haplogroups

Three types of DNA tests

Autosomal DNA test looks at the DNA

from ALL your ancestors

used by permission from http://stevemorse.org/genetealogy/dna.htm

Autosomal Inheritance by Steve Morse

Inheritance from 8 g-grandparents, courtesy of Angie Bush

Make a DNA chart from grandparents at https://www.legacytree.com/inheritance

Relationship Chart from ISOGG wiki http://www.isogg.org/wiki/Autosomal_DNA_statistics

Your autosomal test data

Why Do A DNA Test?

  • Am I who I think I am?
  • Ancestry Composition, as expected?
  • Find some distant cousins
  • Break a Genealogical Brick Wall

from Cece Moore's blog at http://www.yourgeneticgenealogist.com/2015/02/switched-at-birth-unravelling-century_27.html

My brother at 23andme.com

My brother at Ancestry.com

My brother at FamilyTreeDNA.com

My brother at GEDmatch.com

My brother at DNA.land

Newly found cousins may have family stories and photos

My 3rd 1R sent me photos of my gg-grandparents

http://blog.kittycooper.com/2013/03/we-have-found-our-ancestor-lars-monsen/

Where to test? It depends ...

  • 23andme.com
  • Ancestry.com
  • FamilyTreeDNA.com

http://blog.kittycooper.com/dna-testing/

The Big Three:

New DNA Test Companies

  • MyHeritage
  • LivingDNA

http://blog.kittycooper.com/other-blogs-and-resources/downloads/

Ancestry DNA is the easiest to use and it finds how you are related to a match

Ancestry has Genetic Communities

Family Tree DNA accepts transfers of data from other testing sites

ftDNA has a Chromosome Browser for Matches

23andme also has a Chromosome Browser for your admix

and you can download the segment data for your ancestry composition

MyHeritage DNA Cousin Matching

Living DNA has a much finer breakdown of ancestral areas in the UK

Health Results: Upload to Promethease.com for $5.00.

For more cousin matches upload to

  1. GEDmatch.com
  2. DNA.land
  3. MyHeritage.com

Also GEDmatch and DNA.land will give you more ancestry composition results

DNA.land ancestry composition for me and my brother

DNA Testing Basics

By Kitty Cooper

DNA Testing Basics

How personal genome tests can help a genealogist

  • 1,209
Loading comments...

More from Kitty Cooper