dna evidence with ancestry

DNA EvidenceUsing DNA to Verify My Ancestry Tree

Jamie Cox

January, 2016

My Background• Using Ancestry for ~ 4 years

• 1130 People on my tree

• Mostly in Georgia, USA

• I’ve Taken the Ancestry DNA test

• Which of my research lines have DNA evidence?

Data Overload• 254 Pages of matches

• (Over 1200 matches)

• Two 2nd cousin matches

• Eight 3rd cousin matches

• 60 DNA Hints

• 620 4th-6th cousin matches

• 19 DNA Circles

• (I have No “New Ancestor Discovery” Circles)

Back to Basics• What areas of my family tree are solidly backed by

DNA evidence?

• I have a lot of DNA matches that don’t match my tree

• Are any areas wrong?

• How to use all this data?

• Ancestry provides very limited tools

• I Decided to make a paper chart

Fan Chart

Grandparents

Great-Grandparents

GG Grandparents

3rd GGrandparents

Mother’s TreeBrick Wall

Father’s Tree

DNA Circle

DNA CircleDNA Hint

DNA CircleDNA Hint

Wow! No Matches

to Paternal Grandfather’s Tree. Uh-Oh.

Chart InterpretationsAbsence of evidence is not evidence of absence

• Am I the Last of the Mohicans?

• What if I’m one of the only living descendants from this family, and there’s no one else to match … or…

• My paternal grandfather’s folks don’t like genealogy/DNA

• Unlucky DNA - My DNA happens to differ so much as to not be a match

• Non-paternity

The Fourth CaseDNA Match No DNA Match

Trees Match DNA Hint or Circle

Mismatch Alert! X

No Tree Match“New Ancestor

Circle” or regular DNA match

unrelated, ignore

Non-PaternityNon-paternity - anytime someone’s actual parent(s) are not who we think they are

• Non-Paternity Events:

• Infidelity

• Rape

• Secret Adoption - a woman pretends a child is hers to protect the actual mother

Non-Paternity RateGeneration Opportunities

for Error

Total Opportunities

for Error1.2% 1.5% 5.0% Years

Ago

You 0 0 0 0% 0% 0% 0Parents 1 1 1 1% 2% 5% 20

Grandparents 2 2 3 4% 4% 14% 40

GG parents 3 4 7 8% 10% 30% 60

GGG parents 4 8 15 17% 20% 54% 80

GGGGp 5 16 31 31% 37% 80% 100

… 6 32 63 53% 61% 96% 120

7 64 127 78% 85% 100% 140

8 128 255 95% 98% 100% 160

Next Steps• Test Family Members’ DNA

• Father (deceased)

• Mother ✔(Helps identify matches as maternal/paternal)

• Siblings ✔(Complete, another random sample of Dad’s DNA, similar results)

• 2nd or 3rd cousins ✔

• I’m looking for “cousins” who may not be cousins

• Cousins on my tree who have done DNA test (Found 4!)

• They don’t match my DNA - non-paternity confirmed

• Y-DNA Testing ✔ - since my straight male line is now in question

• NO matches to my surname

Help From ancestry.com• We need help with all this data, please

• Ancestry should have drawn that DNA chart for me

• need WAY more searching & sorting options

• User-assignable tags & categories

• AND/OR/NOT filters

• Download DNA matches to spreadsheet