Exploring the advantages of amplifying the entire extract versus splitting the extract and interpreting replicates using a continuous model of interpretation

Previous studies examining whether splitting the DNA extract for replicate amplification versus maximizing the template available for a ‘one-shot’ amplification either examined the benefits of using replicates (without a comparison to a single amplification), or used semi-continuous probabilistic software that ignores peak height information. In this study, we use a fully continuous probabilistic genotyping software to compare the effectiveness of amplifying a single sample compared to splitting the sample and conducting a joint analysis of replicate amplifications. We show that the one-shot approach is marginally better than splitting the DNA extract across a range of contributor numbers and template amounts. Where there is unexpected peak height variability or drop-in within the profile not modelled during interpretation, a replicate approach may be better.