Tales of unexpected DNA data

This week Jesse Bloom of Seattle’s Fred Hutchinson Cancer Research has published an account of some DNA sequence data he located in an internet archive, despite it having been removed from the US NIH’s Sequence Read Archive. He tells Roland Pease of its significance to our understanding of the beginning of the Covid pandemic, but also, of more general interest, to what it might tell scientists about the full availability of relevant virological evidence.Elsewhere, Elena Zavala of the Max Planck Institute for Evolutionary Anthropology in Leipzig has been using new techniques for sequencing tiny fragments of mitochondrial DNA found in layers of mud to trace a long narrative of different evolutionary species of human and animal and their changing fortunes. As she describes in a paper published in Nature, sediments from different depths of the floor of the famous Denisova cave tell a long story of different humans (Denisovan and Neanderthal), bears, hyenas and other animals living there over different periods in the last 250 thousand years.Over in the journal Science, several papers describe a new type of early hominin found in Nesher Rambla, Israel, that may be yet another instance of a human species that didn’t quite make it. As Marta Lahr, professor in human evolutionary biology at Cambridge University tells Roland the new findings all point to the bigger question – given the similar ages, technologies, and even neighbourhoods that all these types of hominin shared, just what was it about our own direct ancestor species that enabled us to take over the world?Since almost the beginning of the Covid pandemic, in some parts of the world, the drug Ivermectin has been repurposed as a therapy against the disease, with some even believing it to convey protection against infection – a situation not without tragic consequences. The evidence for any meaningful effect has been less than obvious to most scientists and health authorities. Not the first controversial drug in the story of Covid-19, the discourse has led to abuse directed at scientists and officials, and scathing arguments across social media. As Oxford University’s PRINCIPLE trial this week begins to include Ivermectin in its investigations, BBC Reality Check’s Jack Goodman reports on the Ivermectin’s tortuous path.(Image: Getty Images)Presenter: Roland Pease Producer: Alex Mansfield