jail logo DNA·VIEW Mixed Stain Calculator

The Stain Calculator is part of DNA·VIEW. It is discussed in the paper Mixed Stain Calculator.
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Case 9
Data for case 9  2000/8/24 8:51
          M     Victim  45-00092 c  J Hoffa
          U    Unknown  45-00090 -  coffin mixture
          S    Suspect  45-00091 c  P Rubirosa

     Matching Odds Summary for case 9
locus CSF1PO 5q33.5-34 Matching Odds = 0.871
locus DQA1   6p21.3    Matching Odds = 4.8
locus THO1   11p15.5   Matching Odds = 2.9
Cumulative Matching Odds = 12.1

Analysis for CSF1PO. Caucasian frequencies
Case is 9 LR = 0.8714
LR = 1 / 12bd
Victim 45-00092
or known source alleles		 8 13
Stain 45-00090 9 10 11 12
V=victim or known
S=suspect
X=exclusion
U=unknown source		 U S U S V V
Allele frequency a=0.0275 b=0.2675 c=0.2575 d=0.3575 e=0.0025 f=0.07
Suspect 45-00091 10 12
# unknown persons, H0 1 print simplify
# unknown persons, H1 2 calculate exit

Analysis for DQA1. Caucasian frequencies
Case is 9 LR = 4.8
LR = [1 / 12e] • (a+2b+2c+2d+2e / {(a+2b)•(d+d+e/2) + a2/3 + b2 + ab}
Victim 45-00092
or known source alleles		 2 4
Stain 45-00090 1•1 2 1•2 4 1•3
V=victim or known
N=null
S=suspect
X=exclusion
U=unknown source		 U V N (=null) V S
Allele frequency a=0.123 b=0.09 c=0.218 d=0.294 e=0.052 f=
Suspect 45-00091 4 1•3
# unknown persons, H0 1 print simplify
# unknown persons, H1 2 calculate exit
Note null: The DQA1 "1•2" allele is coded as "null" in many mixtures including this one to reflect the way that the DQA1 dot blot strip works. Recall that the sensitivities of the dots on the strip are
1234C1•1 1•2 1•3 41•3all but 1•3
Therefore, for a case like this one the strips would not have told us whether 1•2 is present in the mixture or not. That means 1•2 behaves effectively as a null allele.