How True Allele Works Part 3 Kinship Paternity






























- Slides: 30
How True. Allele® Works (Part 3) Kinship, Paternity and Missing Persons Cybergenetics Webinar December, 2014 Mark W Perlin, Ph. D, MD, Ph. D Cybergenetics, Pittsburgh, PA Cybergenetics © 2003 -2014
Kinship Task. Infer genotypes and match them Tool. Bayes theorem Data. Genotypes of family members
Bayes theorem
Pedigree father F mother M person X child 1 C 1 spouse S child 2 child 3 C 2 C 3
Prior probability How a variable is affected father F aa mother M ab person X
Prior probability father F aa mother M bc person X Punnett square b c a ab ac X = ab 1/2 ac 1/2
Likelihood How a variable affects others person X spouse S bb child C ab
Likelihood person spouse X S aa bb aa child aa C ab
Posterior probability father F aa mother M bc person spouse X S bb child C ab
Posterior probability father F aa mother M bc person spouse X S bb child C ab
Genotype comparison alleged person A ab father F aa mother M bc person spouse X S bb child C ab
Bayes theorem, second round Hypothesis: The missing and reference persons are the same individual Posterior to prior genotype probability ratio (Essen-Moller, 1938).
Match strength
Paternity biological father X spouse S child C
Paternity genotype D 7 S 820
Genotype comparison alleged father biological father A X spouse S child C
Paternity index 10, 10 LR = 3. 28 log(LR) = 0. 52
LR = 258, 000 log(LR) = 5. 41 Paternity
Maternity question biological mother X child C alleged mothers A 1 A 4 A 2 A 5 A 3 A 6
Biological mother genotype biological mother X child C
Identifying the mother A 1 A 2 A 3 A 4 A 5 A 6
Missing person 1 person X child 1 C 1 1+2 child 3 C 2 C 3 1+2+3
Children + Spouse 1 person X child 1 C 1 spouse S child 2 child 3 C 2 C 3 1+2+3
Parents + Children father F mother M person X child 1 C 1 1 1+2 child 3 C 2 C 3 1+2+3
Parents + Children + Spouse father F mother M person X child 1 C 1 spouse S child 2 child 3 C 2 C 3 1 1+2+3
DNA mixture
Mixture + Kinship father F person X
Mixture + Kinship genotypes CSF 1 PO Separated minor contributor Kinship inferred son Random person
Contributor genotype match LR = 39, 700 log(LR) = 4. 60 mixture kinship population -18. 00 -20. 58 -20. 66 -20. 76 -22. 00 -24. 97 -26. 00 -28. 00
How True. Allele Works Part 1, 16 -Oct-2014 Genotype modeling and the likelihood ratio Part 2, 20 -Nov-2014 Degraded DNA and allele dropout Part 3, 18 -Dec-2014 Kinship, paternity and missing persons Part 4, 15 -Jan-2015 Genotype database and DNA investigation http: //www. cybgen. com/information/webinar/page. shtml perlin@cybgen. com