June 2020    
  UChicago scientists continue working diligently to understand and combat COVID-19. Read about the science, find answers to your questions about the coronavirus, and stay up-to-date with University efforts to protect the community and beyond.  
  Straight to the source  
  Much of what scientists “know” about ancient genetics comes from assumptions, mathematical models, and extrapolation from studying modern genes and working backward. But now that geneticists can recover DNA from bones and teeth hundreds of thousands of years old, they can collect snapshots of organisms throughout time and make direct comparisons.  
  The study of ancient DNA is still relatively new. There are only a few dozen dedicated labs around the world—including a new one at UChicago: Maanasa Raghavan’s GenSCAPE Lab.  
  Enduring ancestry  
Bronze Age tower
  The s’Orcu ’e Tueri nuraghi, a Sardinian Bronze Age stone tower dating to the mid-to-late second millennium BC. (Photo courtesy Gruppo Grotte Ogliastra)  
  The Italian island of Sardinia has one of the world’s highest concentrations of centenarians.  
  Sardinia is popular for genetic studies: its inhabitants have both unusual longevity and higher than average rates of certain diseases. Understanding ancient Sardinian genetics could provide context for contemporary studies of gene variants, so scientists analyzed DNA from the remains of 70 Sardinians spanning 6,000 years. They found that the island’s ancestry was stable throughout much of the Bronze Age, unlike mainland Europe, where ancestry changed with continental migration. This historical framework offers insights on gene flow and its relationship to human health.  
  Yesterday’s news  
Ancient DNA analysis shows that the people who built Stonehenge were almost completely replaced by a mainland European group that arrived in Britain 4,500 years ago. The genetic change was swift by archaeological standards—over a few hundred years.
Comparisons between modern human and Neanderthal DNA suggest our species had an on-again, off-again relationship.
Scientists have created a portrait of a teenage Denisovan hominid using epigenetic markers to reconstruct her skeleton, but skeptics question the accuracy of the process.
  Resinating science  
Mosquito in amber
  An ancient mosquito trapped in amber served as the source for dinosaur DNA in the movie Jurassic Park (1993), based on the 1990 book by Michael Crichton.  
  In Jurassic Park, scientists cloned dinosaurs using DNA from an amber-encased mosquito.  
  Author Michael Crichton’s plot device merged fact and fantasy. In 1982 an entomologist found a fly in amber thought to be 40 million years old, and some speculated that its DNA might be recoverable. Before the book was published, Crichton met with the bug expert, whose research had struck a chord. The rest is Hollywood history.  
  A day before the film premiered, another team announced the successful DNA extraction from a 130-million-year-old resin-trapped weevil, but it turned out to be contamination. In 2012 scientists determined that DNA can’t survive longer than 6.8 million years, so resurrecting dinosaurs is pure science fiction. Woolly mammoths, however, are still possible—in theory.  
  In case you missed it  
Skeeterish: Scientists attack mosquitoes at the human, bug, and microbe levels.
Cosmic inflation: How fast is the universe expanding? Depends on whom you ask.
  Support UChicago biological sciences.  
  COVID 2025: Our World in the Next 5 Years is a video series in which leading scholars discuss how the coronavirus will change our world and what steps are crucial now to shaping that future.

Sign up to receive µChicago monthly.