A short interspersed nuclear element-based quantitative PCR assay for simultaneous human and dog DNA detection and quantification

This study aimed to develop a quantitative PCR assay to simultaneously quantify human and dog DNA in a multispecies mixture to inform downstream analyses in routine forensic casework and scientific research. The human target is the Yb8 element, which has approximately 2000 copies per cell, and the canine target is the SINEC_Cf element, which has approximately 200,000 copies per cell. The internal positive control is a universal exogenous assay consisting of forward and reverse primers, a NED-labeled probe with an MGBNFQ quencher and a 65-bp synthetic template. Results suggest a potentially robust assay with a fast run time and a high degree of sensitivity, precision and species specificity, with direct application to domestic pet samples in veterinary genetics and forensics. The authors developed a fast, sensitive and precise TaqMan™ probe-based quantitative PCR assay targeting species-specific short interspersed nuclear elements for simultaneous absolute quantification of human and dog DNA via a standard curve for use in forensic investigation. An assessment of the assay's performance was conducted using single-source samples, mixtures and various domestic pet samples.