Human blood from a mosquito's lunch can be used as forensic evidence.

Image: Flickr/dr_rellingAnyone who's ever watched Jurassic Park knows that blood-sucking insects can, in principle, be sources of DNA of their prey. But how reliably? Can living insects, perhaps, be sources of DNA evidence used to solve crimes? Well, according to this study, they can! Here, scientists collected mosquitos from two homes, as well as saliva samples from the people who lived there. From 26 female mosquitos, the scientists were able to collect DNA profiles of 11 people that correlated with the saliva samples. The evidence was strong enough for the scientists to urge investigators "to collect these insects indoors where crimes were committed, because it may be possible to find intact genetic profiles of suspects ... for later comparison to identify an offender and/or exclude suspects." This just might be the first reason I've heard of to be happy your home has mosquitoes.Trace samples of human blood in mosquitoes as a forensic investigation tool. "Investigations of any type of crime invariably starts at the crime scene by collecting evidence. Thus, the purpose of this research was to collect and analyze an entomological trace from an environment that is similar to those of indoor crime scenes. Hematophagous mosquitoes were collected from two residential units; saliva of volunteers that were residents in the units was also collected for genetic analysis as reference samples. We examined the allele frequencies of 15 short tandem repeat loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA) and amelogenin. A total of 26 female hematophagous mosquitoes were identified as Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus; we were able to obtain 11 forensically valid genetic profiles, with a minimum of 0.028203 ng/μL of human DNA. Thus, the results of this study showed that it was possible to correlate human genetic information from mosquitoes with the volunteer reference samples, which validates the use of this information as forensic evidence. Furthermore, we observed mixed genetic profiles from one mosquito. Therefore, it is clearly important to collect these insects indoors where crimes were committed, because it may be possible to find intact genetic profiles of suspects in the blood found in the digestive tract of hematophagous mosquitoes for later comparison to identify an offender and/or exclude suspects." Related content: NCBI ROFL: Beer Consumption Increases Human Attractiveness to Malaria Mosquitoes. NCBI ROFL: Nothing like a thin coat of earwax to keep the bugs away.Science that makes you itchy just thinking about it.