DNA Testing for Genealogy - Eastbourne Family History Society 01 August 2019 Donna Rutherford
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• Eastbourne Family History Society DNA Testing for • 01 August 2019 Genealogy • Donna Rutherford
PDF Version
DNA Testing • Who has done a DNA test? • A DNA test should come with warnings! • Disclaimer
What is DNA (our “genetic code”)
We have 23 pairs of chromosomes (46 in total) – one set
from our Mother, one set from our Father.
• Chromosomes 1-22 are called the autosomes
• Chromosomes 23 are sometimes called the sex
chromosomes.
• A male has an X Chromosome from their mother and a Y
Chromosome from their father (XY)
• A female has an X Chromosome from their mother and
another X Chromosome from their father (XX)
Types of
DNA tests
• Autosomal (atDNA) DNA on the chromosomes 1-22
• Most useful for general genealogy purposes. Both maternal/paternal, for about
5-6 generations (ftDNA, Ancestry, 23andMe, MyHeritage)
• Y DNA (Y Chromosome) – or sometimes called chromosome 23 – fathers fathers
fathers line, “deep ancestry” – most commonly tested at ftDNA
• 2 types STR (markers) and SNP (SNP Packs / Big Y)
• Provides a Haplogroup
• Mitochondrial DNA (mtDNA) – mothers mothers mothers line – only passed down
by mothers (but all children, boys & girls)
• Not on chromosomes, but surrounds the nucleus of a cell, “deep ancestry”,
most commonly tested at ftDNA
• Provides a Haplogroup
How does an atDNA test work • Your saliva sample is sent to a lab for analysis • The test locates specific areas of DNA throughout the 22 (44) autosomal chromosomes. • At each of these locations the test works out what “code” you have – this can be an A, T, C, G. (Adenine, Thymine, Cytosine and Guanine) • Your code is represented in a large text file – location name, code from your maternal and paternal chromosome (test can not work out which side) • If you have long segments of code in common with someone else, they are likely closely related to you. • BUT there are rules (minimum segment length and amount of shared DNA)
How does DNA get inherited (“Recombination”)
• Main 4 companies offering autosomal
DNA tests with ethnicity and cousin
matching
• ANCESTRY
Which companies
• FtDNA (also Y & mtDNA) offer DNA tests
• MY HERITAGE
• 23andME (will give haplogroups)
One more company • LivingDNA (UK based) • Has British Regional Breakdown • Irish/German/ other projects underway • Rolling out cousin matching (Family Networks) • Partnership with FMP • Will give haplogroups (add- on)
Ethnicity Estimates
• Finding your ethnicity from a DNA autosomal test
• These are all estimated by comparing your DNA to living
people – modern populations who have proven ancestry is Italian Sweden
selected areas.
Questions most
often asked
• Which one is Finland
most accurate?
• Which one is
Chinese
correct?
Answer: the one you
like the best!
Middle East
*however updates continue to roll out by the test companies as they
increase their reference populations and tweak their matching
algorithms and calculations
Generally accepted that you can be fairly certain of ethnicity at the
continental level. North &
Companies periodically update their Ethnicity estimates Central
AmericaHow can DNA help
with Genealogy
DNA MATCHES (DNA COUSINS)
Most people get hundreds if not
thousands of matches.
• 4th cousins & closer
➢ Early 2015 – 32
➢ 18 months ago – 185
➢ This week – 380
• People from endogamous populations
will get many more matches
This Photo by Unknown Author is licensed under CC BY-SAWhat can I do with DNA matches? • Find biological family • Contact newly found cousins • Using your DNA matches you can start to confirm your family tree, or breakdown brickwalls you walls you have • Sometimes your DNA matches might solve a mystery, or might actually create a mystery • We need to identify our matches
Measuring DNA
• The amount of DNA you
share with a match gives an
indication of how long ago
you may share a common
ancestor
• The more DNA you share –
the closer your relationship
is
• Usually shown in
centimorgans
• A Complex
measurement of DNA
in common
• Sometimes shown as a
percentage rather
than cM This Photo by Unknown Author is licensed under CC BY-NC-NDMatch List
DNA Painter Tools Site – shared cM Project
https://dnapainter.com/toolsSleuthing • Not Stalking • Use Profile clues • Social Media • Google • People finder sites • Obituaries • (think creatively) • Trees on other sites TEST TAKERS HAVE THE RIGHT TO PRIVACY!! USE SHARED MATCHES
Shared
matches
Must be my fathers sideShared Matches
• Cluster together matches
• See Genetic Affairs
• https://geneticaffairs.com/
• OR built in at My Heritage
• Dana Leeds method
• https://www.danaleeds.com/leeds-method-
dna/
• Use Ancestry coloured buttons
• Common Ancestor of cluster is your common
ancestor
• To find the Common Ancestor build trees!
DO GENEALOGY• Put all the shared
matches into a tree
• Build out the tree
using info from your
sleuthing, hints, etc..
• Keep this tree private
• GOAL: Find the
common ancestor
quickly
Building Quick & Dirty TreesConfirm your
common ancestor
• Check the cM supports the relationship
• Upload to other sites for more matching (or
GEDMatch – public DNA sharing site)
• Consider using WATO (What are the Odds) for
sticky problems – a third party Hypothesis tool
• https://dnapainter.com/tools/probability
• Add your match(es) to your tree
• Do some Chromosome Painting (excl. Ancestry
matches) – need segment data
• https://dnapainter.com/
AND REPEAT
AND REPEATThe Hull • A mysterious group of matches were on my lists that all had families from Hull. • My mum’s grandfather was from Hull • I combined all the family trees for the group of matches to find out who they all descended from • Then I took a look at the 1871 census to see where the ancestors of mystery matches lived 4 Sherwood Square, 2 Sherwood Square, Marvel Street, Marvel Street, Sculcoates, Sculcoates, HULL HULL
Success Stories – Elizabeth Smith
in Lincolnshire
• 3 x Great Grandmother – Elizabeth Smith
• Found a DNA match that was a descendant of her
twin (in Iowa, USA)
• We didn’t know she had a twin!
• You can read about that on an Ancestry blog
• https://blogs.ancestry.com/ancestry/2016/06/20/dn
a-how-it-renewed-my-passion-for-family-history/Success Stories – William Perrot was really William Crann • The Crann family emigrated from Dorset to New Zealand & Newfoundland • William was born illegitimate and used his mothers name • Descendants of William Perrott (and his Crann siblings) all have DNA matches to Crann family in Newfoundland
Success Stories – Jennifer’s Story • Jennifer was looking for an unknown father (she had a birth certificate name only) • I could see she matched me on my Roberts side of the tree (4th cousin match) • Working forwards in my Roberts tree and upwards from the name on her birth certificate, I found a potential couple – George Roberts married a woman from an early polish settler family • Ethnicity confirmed Jennifer had Eastern European ethnicity (Clue/Hint) • 2 Hours later I sent her a photo of our 2x Great Grandfathers standing next to each other (their parents were our MRCA
Success Stories – Adoptees & Foundlings
Cold Cases & Law Enforcement
• Early 2018 news broke about GEDMatch being used to solve a DNA
“Doe” case (“Buckskin Girl”) and also the Golden State Killer
• Law Enforcement Kits could be uploaded at GEDMatch could be for
Violent Crimes (sexual assault) or murder (for matching) – many people
were in favour of this
• There was continued success at GEDMatch
• January 2019 ftDNA allowed Law Enforcements into their database (and
opted out all European Kits due to GDPR) – again just for matching
• May 2019 – GEDMatch allowed a LE kit for a serious assault (but not
murder & not rape)
• Consequence of concern from the community re Terms of Service & Informed
Consent
• All kits now opted out (with 10’s of thousands opted back in, but nowhere near
the number that were there for LE to use before)
• There are no regulations in place for this work
How do you feel about these very sensitive ethical dilemmas?Where can I get help
• ISOGG wiki (join ISOGG for free)
https://isogg.org/wiki/Wiki_Welcome_Page
• Facebook groups
https://www.facebook.com/groups/AncestryUKDNA/
• YouTube videos
• For example
https://www.youtube.com/channel/UCHnW2NAfP
IA2KUipZ_PlUlw
• Testing Company help pages
• ftDNA, Ancestry, 23andMe, My Heritage
https://www.familytreedna.com/learn/dna-basics/PDF Version
Thank you
• Donna Rutherford
• Web: donnarutherford.com
• Twitter: @donnasr
• Mail: ds.rutherford@gmail.com
• Facebook Group:
https://www.facebook.com/groups/AncestryUKDNA/
• Images are used under creative commons licences, fair use
policies, and for educational purposes.
• Family images are copyright Donna Rutherford
This Photo by Unknown Author is licensed under CC BY-SA-NCYou can also read
