• Question: 1.Has there ever been a time when you took a test sample and could not identify the problem?

    Asked by anon-254933 to Alice on 19 May 2020.
    • Photo: Alice Burleigh

      Alice Burleigh answered on 19 May 2020:

      Hi Thalia and Theo! Great question, and yes this can happen quite a lot! Because the patients we test often have very rare or sometimes even totally new diseases, it’s usually hard to find the cause of the problem.

      The way we approach the problem is the same way you would try to find something you’d lost, let’s say you lost your phone. First- you check the obvious places, the places you think you might have left it… school bag? sofa? pocket? The first thing we do is check the genes that we think might be causing the problem. Sometimes we get lucky and have saved ourselves a lot of time, but often we can’t find anything interesting, so we have to move onto the next stage. Your phone wasn’t where you thought it was, so now you search all the rooms in the house that you have been in recently. At this stage, we look at every gene in the body that codes for a protein, known as whole exome sequencing. Much like you would probably find your phone at this stage, we can usually find the problem here, as the illness is usually caused by a protein in the body going wrong. If not, we can try whole genome sequencing, where we investigate ALL of the patient’s DNA. You’re now thoroughly searching every single place in the whole house for your phone! This gives us loads of useful information about the patient, but is very time consuming and expensive, so is the last resort. If the disease is genetic, we should be able to find the answer here.

      If we’re still stuck, the investigations might be passed onto a different specialist lab, because if we find nothing unusual in the patient’s DNA, the disease might not be genetic. So to answer your question- yes, there are plenty of times where we can’t find the answer, however progressing on to a more thorough investigation usually does the trick, or at least gives us a better idea of what to try next! This same principle applies across all types of science, and is what makes research so interesting.

Comments

  • Photo: anon-254933

    anon-254933 commented on :

    Research definitely does sound interesting! Also thank you for your great examples. It helped me understand thoroughly what you were talking about.

  • Photo: Louisa

    Louisa commented on :

    Thanks for your question, Thalia & Theo! Samples get submitted to the hospital everyday and doctors ask for a list of tests to be performed. Doctors will have a suspicion of what might be wrong from the description of a patient’s symptoms, or they might want to do some checks to ‘rule out’ certain diseases. However, sometimes these first tests may not give us an answer, so we need to do other follow-up tests and sometimes specialised tests to investigate. Alice explained it in a very nice way, that we search for something in the more obvious places first! It is important to also remember that other information can help us understand the reasons why we see a particular set of results, for example, imaging, information about symptoms, and how quickly there was a change in levels compared to the last time a sample was taken.