Highlights
- •A tool to simulate single source and mixed profiles.
- •Peak heights follow a log normal or gamma distribution.
- •Contributors may be related according to a pedigree.
- •An R package named simDNAmixtures is freely available from CRAN.
Abstract
Simulation studies play an important role in the study of probabilistic genotyping
systems, as a low cost and fast alternative to in vitro studies. With ongoing calls
for further study of the behaviour of probabilistic genotyping systems, there is a
continuous need for such studies. In most cases, researchers use simplified models,
for example ignoring complexities such as peak height variability due to lack of availability
of advanced tools. We fill this void and describe a tool that can simulate DNA profiles
in silico for the validation and investigation of probabilistic genotyping software.
Contributor genotypes are simulated by randomly sampling alleles from selected allele
frequencies. Some or all contributors may be related to a pedigree and the genotypes
of non-founders are obtained by random gene dropping. The number of contributors per
profile, and ranges for parameters such as DNA template amount and degradation parameters
can be configured. Peak height variability is modelled using a lognormal distribution
or a gamma distribution. Profile behaviour of simulated profiles is shown to be broadly
similar to laboratory generated profiles though the latter shows more variation. Simulation
studies do not remove the need for experimental data. The tool has been made available
as an R-package named simDNAmixtures.
Keywords
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Article info
Publication history
Published online: July 07, 2022
Accepted:
July 5,
2022
Received in revised form:
June 22,
2022
Received:
May 10,
2022
Identification
Copyright
© 2022 Elsevier B.V. All rights reserved.
