Cross-species amplification from non-human primate DNAs in commercial human DNA assay kits

Species specificity of commercial human DNA quantification kits and short tandem repeat (STR) profiling kits was examined using primate DNA samples. These samples comprised 33 individuals from eight primate species, each with gender and kinship data, including human (Homo sapiens), chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla), and orangutan (Pongo pygmaeus) of Hominidae family, and Japanese macaque (Macaca fuscata), long-tailed macaque (Macaca fascicularis), hamadryas baboon (Papio hamadryas), and savannah monkey (Chlorocebus sp.) of Cercopithecidae family. The findings revealed varying levels of cross-species amplifications in all non-human DNA samples that correlated with their evolutionary proximity to humans, both kit types. Moreover, cross-species amplification, including female DNA samples, was observed in a Y-chromosomal STR profiling kit. Additionally, species specificity differed among the commercial kits examined. The cross-species amplification data presented in this study offer valuable assistance in interpreting the results of individual human identification in forensic cases involving non-human primates.