A newly discovered technique could tell us what diseases killed off our ancestors — providing us with more information than we've ever had before. So what exactly infected this 500-year-old Peruvian mummy?
Previous research into ancient diseases has heavily relied on amplifying microbe DNA, a method prone to contamination, and one which could only confirm the presence of the pathogen, and not whether the person was infected or not. Or else, by using immunoassays — which are likewise easily contaminated, and require searching for specific pathogens.
Angelique Corthals and her team instead turned to protein analysis, looking for the immune systems response in samples taken from the lips of Andean Inca mummies. They separated out the proteins from the DNA, and then ran them through a high-resolution mass spectrometer — a technique called shotgun proteomics. The results from the mass spectrometer were then compared against a human protein database.
The analysis showed evidence of Mycobacterium sp. — in other words, a lung infection, a diagnosis that seems supported by the inflammation they found on a CT scan. That's right: They forensically solved what infected a 500 year old mummy.
This technique has the advantage of longevity, as proteins can survive in remains for a substantial amount of time, as well as being less likely to be contaminated.
So, what's the next dead person we can solve mysteries about? Anyone know where Alexander the Great's corpse is?
Correction: An earlier version of this article stated that the research discovered what killed the mummy, that was in error. The mummies were in fact sacrifices to to Pachamama, the earth goddess. What this technique detected was that she had a lung infection at the time. I deeply regret this error - sorry about that folks. Bad science blogger, no cookie.