Rachel Feltman reports in the WaPo:
A new study suggests that the microbes present on pubic hair -- which vary from person to person -- could be used as evidence in sexual assault cases. This particular research is in its early stages, so you probably won't hear about genital microbes in a courtroom anytime soon. But the study is just one example of the effort to turn the incredible diversity of the bacteria that live on human beings into a high-tech forensic toolkit.* * *The researchers, led by Silvana Tridico from Murdoch University, took scalp and pubic hair samples from seven individuals (three male and four female, with one co-habitating couple in the mix). While hair from the head had around 50 kinds of bacteria a pop, and seemed to be influenced by the environment, pubic hairs had over 70 kinds of bacteria each, which were highly individualized. That's in line with previous studies on the vaginal microbiome, which has shown an unexpected diversity distinguishing one individual from another.
"The advent of DNA profiling has resulted in an increase of sexual offenders using condoms, which they take away, post-assault," Tridico said in a statement. "The implication of this present study is that the transfer of bacteria between victim and offender, in rape cases, may provide a new way of linking the offender to the victim, in instances in which no human DNA is transferred."