Friday, August 25, 2006 - 01:10
Like biology, all bioinformatics is based on the idea that living things shared a common ancestor. I have posted, and will post other articles that test that notion, but for the moment, we're going to use that idea as a starting point in today's quest. If we agree that we have a common ancestor, then we can use that idea as a basis to ask some interesting questions about our genomes. For, example, we know that genomes change over time - we've looked at single nucleotide changes here and here, and we've seen that large chunks of DNA can move around here. So, it's interesting to consider how often different regions of DNA change relative to each other. A few weeks ago we starting monkeying around with comparing human and primate sequences of mitochondrial DNA Well, we're not done. If you'd like to take a quick tour, here is a list of places that we've been and sequences we've explored. Revisiting our blast results Click the image to see a larger version. This image shows where the mitochondrial DNA sequences of humans, bonobo chimps, chimpanzees, and gorillas match. A red bar indicates where the DNA sequences are very similar. Other colors or gaps show regions that are less similar or even missing from one or more sequences. I circled 3 segments in this image and now, here's your chance to interpret the results and make a guess about what the results are telling you. Think about why the sequences in section 2 show a different result than the sequences in section 3. It might be helpful to go ahead and do the experiment yourself, so that you can identify the matching sequences, the instructions are here and there are some helpful hints here. Can you explain the results? Let me know what you find!