Proving Genomic Changes and Evolution
Amazing. One small piece of DNA. Using advanced, repeating gene sequencing techniques, the researchers generated a precise genomic sequence. The DNA belongs to a young girl. A girl who lived well over 50,000 years ago in a cave in Siberia. Scientists call her a Denisovan because that’s the name of the cave. They were near relatives to Neanderthals – see here for a broader discussion in Scientific American. Now, by comparing the old and current genomes, the team can see how much we’ve changed from this ancient person from over 50,000 years. The answer? Not really that much change.
The new work is by researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The work and paper are groundbreaking because the researchers figured out how to use a single strand of DNA to generate the sequence. What do other researchers think about the work of Matthias Meyer and others? “Meyer and the consortium have set up the field of ancient DNA to be revolutionized—again,” says Beth Shapiro, an evolutionary biologist at the University of California, Santa Cruz, who was not part of the team. Evolutionary geneticist Sarah Tishkoff of the University of Pennsylvania agrees: “It’s really going to move the field forward.”
Why does that matter? Because many more fossils include single strands pieces of old DNA. Think pieces of amber and Jurassic Park. What’s next for the research team? "Back in [the lab at Max Plank in Leipzig], the mood is upbeat, as researchers pull fossil samples off the shelf to test anew with “Matthias’s method.” First on the [team leader’s list}: Neandertal bone samples, to try to produce a Neandertal genome to rival that of the little Denisovan girl." That is, they are going to try more museumomics.
Why do lawyers care? Suppose the question is whether "toxins" are causing multi-generational changes to genomes. Suppose the current plaintiff has lockets of hair from her life before exposure to the toxin, and/or knows the locations for the graves of 3 or 4 generations of predecessors. We could be looking at generation to generation sequencing and comparison. Suppose the plaintiff is 65 year old woman with breast cancer, and a daughter and a granddaughter. Suppose there also are sequences for the daughter and the granddaughter. Will that generate "proof" of a cause if breast cancer shows up in the daughter or granddaughter ? I’m sure I don’t know, but it’s interesting to think about the possibilities ahead.