Highlights
- •Mixtures of a mother, father, child trio are examined using the software STRmix™.
- •Parent/child allele sharing often results in artificially high or low LRs.
- •User-informed mixture proportions and an assumed donor parent assists interpretation.
- •The distribution of LRs for true and false donors is reported.
Abstract
We report the interpretation of three-person mixed DNA profiles constructed from DNA
from one mother, father, and child trio using the probabilistic genotyping software
STRmix™. A total of 40 mixtures were examined, with varying total template and mixture
proportions of the three contributors. In addition, mixtures were artificially degraded
at four different rates to test the effects of degradation on the interpretation of
mother, father and child trios. A total of 560 STRmix™ analyses were undertaken, examining
four different interpretation strategies. Reasonable results were only achieved by
conditioning on one parent as an assumed donor and applying a user-informed prior
to the mixture proportion of both parents.
For each of the 40 amplified mixtures, 10,000 non-donors were compared, conditioning
on one parent and applying a user-informed prior to the mixture proportion of both
parents. This leads to 800,000 non-donor tests.
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Article info
Publication history
Published online: October 11, 2019
Accepted:
October 5,
2019
Received in revised form:
September 11,
2019
Received:
July 10,
2019
Identification
Copyright
© 2019 Elsevier B.V. All rights reserved.
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- Erratum to “The interpretation of mixed DNA profiles from a mother, father, and child trio” [Forensic Sci. Int.: Genet. (2020) 102175]Forensic Science International: GeneticsVol. 49
