A molecular exploration of human DNA/RNA co-extracted from the palmar surface of the hands and fingers.

•Origin of touch DNA and background levels of foreign DNA on human hands are debated.•We performed DNA/RNA co-analysis of palmar samples to address both issues.•15% of the samples included tissues other than skin, according to mRNA profiling.•Samples including tissues other than skin gave significantly higher DNA yields.•DNA quantity/integrity was higher in males; prevalence of DNA mixtures in females.