10.26091/ESRNZ.11833548.v1 Michael D. Coble Michael D. Coble Jo-Anne Bright Jo-Anne Bright John S. Buckleton John S. Buckleton James M. Curran James M. Curran Uncertainty in the number of contributors in the proposed new CODIS set Institute of Environmental Science and Research 2020 Forensic DNA Mixed DNA profiles Interpretation Forensic Biology 2020-04-30 02:46:27 Journal contribution https://research.esr.cri.nz/articles/journal_contribution/Uncertainty_in_the_number_of_contributors_in_the_proposed_new_CODIS_set/11833548 <p>The probability that multiple contributors are detected within a forensic DNA profile improves as more highly polymorphic loci are analysed. The assignment of the correct number of contributors to a profile is important when interpreting the DNA profiles. In this work we investigate the probability of a mixed DNA profile appearing as having originated from a fewer number of contributors for the African American, Asian, Caucasian and Hispanic US populations. We investigate a range of locus configurations from the proposed new CODIS set. These theoretical calculations are based on allele frequencies only and ignore peak heights. We show that the probability of a higher order mixture (five or six contributors) appearing as having originated from one less individual is high. This probability decreases as the number of loci tested increases. </p>