Autosomal DNA Testing For Genetic Genealogy Information From My FTDNA Family Finder Kits
Autosomal DNA Testing
For Genetic Genealogy
Information From My
FTDNA Family Finder Kits
FTDNA Family Finder
Family Finder uses autosomal DNA (inherited from both the mother and father, four
grandparents, eight great-grandparents, etc.)to provide you a breakdown of your ethnic percentages and connect you with relatives descended from any of your ancestral lines within approximately the last 5 generations.
FTDNA Family Finder
Matches
Chromosome Map
Known Relations
My Family Finder Tests
Me Wife
Son2 Son 3 Dau 1 Dau 2Son1
FIL MILMom
gdau1
gson1
gson2
gson3
Paper Trail
YDNA
MTDNA
All Lines
Two Sides
46 chromosomes
2 Of You
2 Lines
PATERNAL MATERNAL
Paired DNA
Haploid Haploid
Diploid
22 Pairs of Autosomes2 Sex Chromosomes
46 TOTAL
A Pair of Autosomes (1-22)You
A Pair of Autosomes (1-22)You
One Person – Two Sides
Paternal Maternal
Two Sides
Two Sides – Every Person
Two Sides
PaternalChromosomes 1-22
MaternalChromosomes 1-22
GF GFGM GM
MOTHERFATHER
CHILD
Are They Related If Segments Overlap on The Same Map?
Answer - Depends Upon Lineages
Two Lineages- One Map
Paternal Grandmother&
Maternal Grandmother
Two Lines - One MapThese Overlaps Are From
DIFFERENT Sides
CHILD
One Lineage– One Map
Maternal Grandmotherand
Maternal Great Grandmother
One Line (Twice) - One MapThese Overlaps Are From
SAME Sides
CHILD
Daughter’s Share with Distant Cousin
Daughter’s Share with Distant Cousin = 1 Paternal Segment and 1 maternal Segment
Paternal
Maternal
WR-kit
Which Line is this Match?
Answer = Either Line
Inheritance
1 Full Glass = 50% of 2 Full Glasses
1 Full Glass = 50% of 2 Full Glasses
1 Full Glass = 50% of 2 Full Glasses
50% 50%
Inheritance
2
1
50% Inheritance
Where’s the 50% On The Map?
Answer – It is the Map
CHILD
50% Inheritance – 1:2
2 Lines
1 Line
MOTHER
Parent/Child Map
Line 1 Line 2
Actual:Composite Of Parent’s Lines
Parent – Paternal and Maternal
Mother-Child Phased MAPChild’s Maternal to Mother’s Lines
Mother-Child Composite MAPChild’s Maternal to Mother’s Lines
YOU
50%50%
To Both Parents
Child – Mother Mapping
Mother’s Paternal
Mother’s Maternal
Jump a Generation to Filter
Mother’s Paternal
Mother’s Maternal
To Both Grandparents
50% MeansEach Generation Reduces Share
Mother to Child
Grandmother to Child
Great-Grandmother to Child
Each Generation Has Less Chancesof Matching
Relation Likelihood of a Match %DNA Shared
1st Cousin 100% 7% - 13%
2nd Cousin >99% 3% - 5%
3rd Cousin >90% .3% - 2%
4th Cousin 50% <1%
5th Cousin 10% sometimes none detectable
6th Cousin <2% often none detectable
What If?50% Less Each Generation
Numbers Do Not Account for Variations
Generations centiMorgans
0 7,768.0
1 3,884.0
2 1,942.0
3 971.0
4 485.5
5 242.8
6 121.4
7 60.7
8 30.3
9 15.2
10 7.6
More Relatives On Some BranchesAlso Affect Distant Matches
Cheaper by the Dozen 2
Variation
1 Full Glass = 50% 2 Full Glasses
1 Full Glass = 50% of 2 Full Glasses
1 Full Glass = 50% of 2 Full Glasses
Variation
1 Full Glass = 50% of 2 Full Glasses
Variation
2/3 and 1/3 Variation
Meiosis – Combining 2 Lines to 1
Meiosis – Combining 2 Lines to 1CROSS-OVER
RESPONSIBLE FOR VARIATION
Cross-Over
Cross-Over Locations
Grandson to Paternal Grandparents
2 Became 1 – Next Gen Down
Son
Grandson
My Wife = ORANGEMy Ancestry = BLUE
Variation In Siblings
Two Lines (Paternal/Maternal)Variations Affect Distant Matches Both Sides
SON 1 Maternal
SON 2 Maternal
SON 3 Maternal
DAU 1 Maternal
DAU 2 Maternal
Mom’s 5th cousin to Us…
5th Cousin’s Kit
My Mother’s Kit
gson3
gson2
gson1
gdau1
gfather
gmother
4 Paternal Grandchildren
25% Location
I Don’t See All My Cousins, Is My Tree Wrong?
Answer – Not All Cousins on Paper, Match Genetically
http://www.genetic-inference.co.uk/blog/2009/11/how-many-ancestors-share-our-dna/
Not All Lines Mix at Crossover
X DNA(no crossover this grandchild)
Cross-Over Not Proportional
Gen 1
Gen 2
Gen 3
Gen 4
Cross-Over Not Proportional
Gen 1
Gen 2
Gen 3
Gen 4
Example of Persistence
To LEC kit
Mom
Me
Son1
GSon1
Recombination, parent-child trios(Autism Genetic Research Exchange)
Crossover Hot Spots
Chromosome 1 crossover locations of my five children, their maternal side
Full Siblings
Sisters
Composite Result of Share
Full Sibling Matches Involve 4 Lines (4 Grandparents)
Father Mother
Sibling Sibling
Sisters
Daughter 1 Paternal
Daughter 2 Paternal
Daughter 1 Maternal
Daughter 2 Maternal
Sisters
Sisters
SistersFULL
HALF
FULL FULL
HALF HALF
Sisters
The Map is Composite (two lines combined into one color)
Phased ResultsSon1 to Dau1 Comparison
Phased ResultsSon1 to Dau1 Comparison
courtesy of www.gedmatch.com
GREEN/BLUE = FULL IDENTICAL
YELLOW/BLUE = HALF IDENTICAL
Full Siblings
courtesy of www.gedmatch.com
Half Siblings
GREEN/BLUE = FULL IDENTICAL
YELLOW/BLUE = HALF IDENTICAL
Phased ResultsSon1 to Dau1 Comparison
CentiMorgans
HALF IBD 3587.10
FULL IBD 7174.20
Paternal 2154.20
Maternal 1819.80
Total 3974.00
Percentage 55.39%
Gedmatch HIR
Gedmatch FIR
Family Finder is a SHARING test
How Much In-Common Do You Share With Another
This is Especially True for Full Siblings Since They Share 4 Lines of DNA
What if? Can’t Test a Parent
Using 1 Sibling to Build a Parent’s Map
Using 2 Siblings to Build a Parent’s Map
Using 3 Siblings to Build a Parent’s Map
Using 4 Siblings to Build a Parent’s Map
Using 5 Siblings to Build a Parent’s Map
COUSINS
COUSINS
SIBLINGS
COUSINS
COUSINS
Variation
VariationVariation
R
RR
COUSINS
805cM
2439cM
Cousins Share - Siblings’ DNA
Siblings’ In-Common DNA
2 Siblings
R
Siblings’ In-Common DNA
2 Siblings
R R
R
Siblings’ In-Common DNA
2 Siblings
R R
R R
R
Siblings’ In-Common DNA
2 Siblings
R R
R R
R R
R
2 Matches, Not 3-Way
B
A C
3-Way Matches
B
A C
SIBLINGS
NEPHEW
COUSINS
Different Views – My View
Different Views – Their View
Mapping Descendents(reverse engineering branches)
Mapping AncestryMy Maternal Grandparents
wmd
RECOMBINED
RECOMBINED
Cousins - 2 Generations
Son 1
PATERNAL SIDE MATERNAL SIDE
GSon 1
PATERNAL SIDE
Son 2
PATERNAL SIDE MATERNAL SIDE
GSon 3
PATERNAL SIDE (Fathers are Siblings)
Cousins = 4 Lines Compared to 4 Lines
GSon 3GSon 1
PATERNAL SIDE (Fathers are Siblings)
FIRST COUSINS
WD
CD
In-Common Segments
WD
CD
~2600cM
~800cM
~300cM
Full Siblings
1st Cousins
2nd Cousins
Examples (Approximate) Sum cMs
~2600cM (2) Full Siblings
~1400cM
~450cM
Doubled Cousins Raise Sums Up
Half Siblings
1st Once Removed
~1400cM
~450cM
Half Sib Descendants Drop Sums Down
Half Siblings
1st Once Removed
2nd or 3rd
Cousins~100-200cM
Predicating
Close and Immediate
Distant
Speculative
Sum of cM
Segment Sizes and Probabilities
Confirmed
My Kit Data, Other Results May Vary
Close and Immediate
Distant
Speculative
Closing
• We Have Two Sides (paternal, maternal)
• We Inherit 50% From Each Side
• We Inherit Each Line By Recombination
• Recombination Produces Variation of Ancestry
• Siblings and Cousins share DNA from both sides (composited together like a pool)
Questions
Web InfoREFERENCES
http://www.familytreedna.com/faq/answers.aspx?id=17
http://www.genetic-inference.co.uk/blog/2009/11/how-many-ancestors-share-our-dna/
http://ongenetics.blogspot.com/2011/02/genetic-genealogy-and-single-segment.html
http://www.ncbi.nlm.nih.gov
SITES AND BLOGS
http://www.dna-testing-adviser.com
http://www.yourgeneticgenealogist.com
http://www.thegeneticgenealogist.com
http://dna-explained.com
http://www.adoptiondna.blogspot.com
http://genealem-geneticgenealogy.blogspot.com
http://www.gedmatch.com
http://www.dnagedcom.com
http://www.dnaadoption.com
http://www.math.mun.ca/~dapike/FF23utils/index.html