A study in humans demonstrated that the expression profiles of the piR-hsa-17770 collectively provided valuable information for discriminating forensically relevant biological fluids, with a panel of 37 candidates achieving a classification error rate of 0.04 in a PLS-DA model [Wang et al. DOI:10.1016/j.fsigen.2019.07.015]. A study in humans identified the piR-hsa-17770 as an absolute specific marker (ASM) for semen, demonstrating high specificity in pairwise comparisons and moderate expression levels [Liu et al. DOI:10.3390/genes13091530].