"Jurassic" reappearance: the lice on the mummy's hair extracts ancient human DNA

Scientists have discovered that human DNA can be extracted from the "glue" of head lice that glued eggs to the hair thousands of years ago, which may provide an important new window for studying the past

In a new study, for the first time, scientists have extracted DNA of the "binder" from hairs extracted from the remains of mummies 1500-2000 years ago

The analysis of this newly discovered ancient DNA-which is of better quality than DNA obtained through other methods-reveals clues to human migration patterns in South America during the pre-Columbian period

Dr.

"In recent years, as we try to understand the migration and diversity of ancient human populations, the demand for DNA samples from ancient human remains has continued to grow

So far, ancient DNA is best extracted from the dense bones inside the skull or teeth, because this provides the best quality samples

Therefore, extracting DNA from the adhesive delivered by the lice is the solution to the problem, especially the lice are usually on the hair and clothes of the mummy in good condition

The research team extracted DNA from a sample of young lice eggs from mummified remains in Argentina

The young egg adhesive sample used for DNA research was found to contain the same concentration of DNA as the tooth, twice the DNA concentration of bone debris, and four times the DNA concentration in the blood of a closer lice sample

Dr.

"We are currently looking for alternative sources of ancient human DNA, and lice young egg adhesive may be one of them

In addition to DNA analysis, scientists can draw conclusions about a person and their living conditions from the location of the lice on the hair and the length of the adhesive tube

Analysis of the DNA extracted from the lice adhesive found and confirmed:

• Gender of each human host

• Three of the mummies are genetically linked to humans in the Amazon region 2000 years ago

  
  

• All the remains of ancient humans studied belong to the mitochondrial lineage of South America

  
  

• The earliest direct evidence of Merkel cell polymavirus (Merkel cell Polymavirus) was found in the DNA of a mummified louse egg glue
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  This virus was discovered in 2008 and is spread by healthy human skin.
  In rare cases, it can enter the human body and cause skin cancer
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  This discovery opened up the possibility of head lice spreading the virus
  .
  

The DNA analysis of these lice confirmed the migration pattern of human lice from the northern Amazon river plain to central and western Argentina (San Juan Andes)

Morphological analysis shows:

• These mummies are likely to be exposed to extremely low temperatures when they die, which may be a factor in their deaths
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  This is shown by the very small gap between the lice on the hair shaft and the scalp
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  The lice rely on the heat of the host's head to maintain the temperature of the eggs, so in a cold environment, the lice will lay their eggs closer to the scalp
  .
  

• Shorter eggs on the hair are associated with older and/or less preserved specimens, as the mixture degrades over time
  .
  

Molecular Biology and Evolution

DOI

10.
1093/molbev/msab351