TranslucentID: Detecting Individuals with High Confidence in Saturated DNA SNP Mixtures

Abstract

High throughput sequencing (HTS) of complex DNA mixtures with single nucleotide polymorphisms (SNPs) panels can identify multiple individuals in forensic DNA mixture samples. SNP mixture analysis relies upon the exclusion of non-contributing individuals with the subset of SNP loci with no detected minor alleles in the mixture. Few, if any, individuals are anticipated to be detectable in saturated mixtures by this mixture analysis approach because of the increased probability of matching random individuals. Being able to identify a subset of the contributors in saturated HTS SNP mixtures is valuable for forensic investigations. A desaturated mixture can be created by treating a set of SNPs with the lowest minor allele ratios as having no minor alleles. Leveraging differences in DNA contributor concentrations in saturated mixtures, we introduce TranslucentID for the identification of a subset of individuals with high confidence who contributed DNA to saturated mixtures by desaturating the mixtures.

Estimating Individual Contributions to Complex DNA SNP Mixtures

“…IdPrism uses the Fast P(RMNE) [32] program to automatically calculate the probability of a random person (man) not excluded P(RMNE) [17,18]. For saturated (i.e., > 70% of loci detected with minor alleles) SNP mixtures, IdPrism uses the TranslucentID [33] program to identify individuals in saturated mixtures that are not detected using standard mixture analysis techniques. The TranslucentID method is a novel approach to the identification of individuals in a saturated mixture that creates a derivative desaturated mixture by treating the SNPs with the lowest mAR values as MM alleles [33].…”

“…For saturated (i.e., > 70% of loci detected with minor alleles) SNP mixtures, IdPrism uses the TranslucentID [33] program to identify individuals in saturated mixtures that are not detected using standard mixture analysis techniques. The TranslucentID method is a novel approach to the identification of individuals in a saturated mixture that creates a derivative desaturated mixture by treating the SNPs with the lowest mAR values as MM alleles [33]. This method was used on the equimolar ten person defined mixture (URK5V:IX-25).…”