• Question: can any genetic information be gained from mutations?

    Asked by lily4 to Rachael, Penny, Jennifer, Jean-Paul, Dave on 10 Jan 2014.
    • Photo: David Christensen

      David Christensen answered on 10 Jan 2014:

      Yes absolutely. Genetic information is gained, lost, and changed by mutations. Mutations can take the form of insertions into DNA which can add and change the information encoded in the DNA, or mutations can be deletions of DNA to lose genetic information, or mutations can just be changes where one small bit of DNA is changed slightly so that the code is affected.

      As mutations in DNA are responsible for all of evolution, a lot of genetic information has been gained and lost throughout our evolution and throughout the evolution of all other plants, animals, bacteria and all living things.

    • Photo: Penelope Mason

      Penelope Mason answered on 10 Jan 2014:

      Hello! If you mean, can we get information about a gene by looking at its mutations, then yes, absolutely – we can find out what the protein does (and doesn’t) do, what bits of the code are necessary for the protein to be functional, what other molecules the protein interacts with and what bits of it it uses to do this, just by mutating the relevant bit and seeing what changes.

      If you meant can we generate new or stronger protein activities by mutation, then yes, as Dave has already said. One interesting example of this is a mutation that causes people to not feel pain. The mutation causes a protein in nerves to work too well – this blocks the pain signals from getting through. Although this means we can study this to find better ways to stop pain, its also a problem for the people with the mutation, as they often fail to notice when they have damaged themselves.

      Another example is the protein p53, which is a tumour suppressor – in other words it acts to block cancer. Mutations in this protein can lead to loss of function (it stops being able to block cancer) and also gain of function (it actively promotes tumours). So you can see how often, although a gain of function might look like it is a good thing, and can give an animal a reproductive advantage (and so be transmitted as an evolutionary advance), this isn’t necessarily the case.

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