Elective: Tracing disease through time

aDNAHave humans always suffered from the same diseases?

Can we trace the factors contributing to people falling ill?

How can this information help us in disease research today?

Molecular science is essential, but with a twist: Sequencing a 21st-century genome may be routine by now, but how do you sequence genomes that are centuries or even millennia old? Take infectious diseases that were - and still have the potential to be - pandemics: Roughly 25 years ago, the entire 1918 Spanish flu genome was finally sequenced after decades of research. This makes all the difference to WHO influenza vaccine development, which is a race against time with every newly mutated flu virus that could kill great numbers of people. So far, researchers have had the upper hand, no small thanks to the genomic information we have gained from sequencing flu viruses.

SARS-CoV-2 is a newly discovered member of the Corona virus family. It arrived from wildlife just a good four years ago, causing the Corona pandemic. The question why patients worldwide do not react in the same way to infection with SARS-CoV-2 led to research and findings for which scientists went back into the Stone Age: The analysis of patient genomes showed that Europeans share alleles with Neanderthals that make them more susceptible or resistant to severe Covid-19. The virus and the disease it causes may be new, but some factors that influence the severity of symptoms in a patient can be traced through time.

Whether you take the Spanish flu or Covid-19: Investigating where, when and how diseases first emerged, why people were susceptible to them, why they are today or why susceptibility has changed, you look back in time to move forward in research.

Putting things into a broader perspective is one of the most important abilities in a researcher, here you can exercise this first-hand.