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

Analysis for DQA1. Caucasian frequencies
Case is 9 Victim 45-00092 Stain 45-00090 V=victim or known Allele frequency Suspect 45-00091 or known source alleles N=null S=suspect X=exclusion U=unknown source LR = 4.8 LR = [1 / 12e] • (a+2b+2c+2d+2e / {(a+2b)•(d+d+e/2) + a2/3 + b2 + ab} 2 4 1•1 2 1•2 4 1•3 U V N (=null) V S a=0.123 b=0.09 c=0.218 d=0.294 e=0.052 f= 4 1•3 1 print simplify 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
 1 2 3 4 C 1•1 1•2 1•3 4 1•3 all 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.