Cleanrooms are used for a number of applications — pharmaceuticals, aerospace, food and beverage, manufacturing, and more. You can also add “solving ancient mysteries” to that list.
A recent Nature Communications study, covered by Newsweek (http://bit.ly/2rJOe3i), details how researchers analyzed DNA from ancient Egyptian mummies to learn more about their ancestry. The groundbreaking study examined DNA from 151 mummified Egyptians, spanning the period from about 1400 B.C. to 400 A.D., during the Roman period. The study showed that genetic material found in the mummies resembled ancient peoples of the Near East and the Levant (an area of the eastern Mediterranean, which includes modern-day Israel and Palestine), rather than modern Egyptians. Genetic links were also found between the ancient Egyptians and Neolithic peoples from modern-day Turkey and Europe — showing that conquests by foreigners such as Alexander the Great may not have had as significant a genetic influence on ancient Egyptians as previously thought.
Mitochondrial DNA was gathered from some of the mummies in a cleanroom facility, which was necessary to avoid contamination with modern genetic material that might skew the results. The mummified remains were treated with UV light to remove recently deposited DNA,
and the exteriors of bones were scraped off in order to access the precious genetic material within.
There have been plenty of other stories in Controlled Environments about cleanrooms being used to extract old and even ancient DNA in order to solve mysteries. In May 2016, a contractor was digging in the backyard of a San Francisco family home when he unexpectedly unearthed the casket of a young child. A UC Davis anthropology professor stepped in after it was announced that the casket of little
“Miranda Eve” would be re-buried with no analysis. Samples of the deceased’s hair were taken to a cleanroom lab, and it was discovered that she was about 2 to 3 years of age and came from European ancestry, most likely the British Isles. Exhaustive research into internment, burial, and genealogical records eventually narrowed the child’s identity down to two possible candidates — living relatives for each were contacted, DNA samples were provided and tested, and finally the child was positively identified as 2-year-old Edith Howard Cook. See http://bit.ly/2rKa4n0 for more.
Cleanroom testing was also used after two college students stumbled upon a human skull during a hike in Washington State in 1996. Researchers found hundreds more bones plus an ancient spear head were found. The body — dubbed “Kennewick Man” by scientists and “The Ancient One” by Native American tribes — had lived over 9,000 years ago. The mystery then focused on the man’s ancestry: was he of European descent, or Native American? A dispute soon arose between the Army Corps of Engineers and local Native American tribes regarding ownership and burial rights. Researchers at the University of Copenhagen sequenced the genome of Kennewick Man and published their results in June 2015, concluding that the man is closely related to modern Native American tribes.