Adult onset condition, those with genetic mutations associated with the disease don’t get it until they’re adults, starts in one place and then it spreads, once it occurs the progression is usually relentless…. what condition am I describing?
Professor Neil Pearce’s point in his talk at the opening session of the International Symposium on ALS/MND was that he was describing both motor neurone disease (MND) and also cancer. Although the conditions are very different, as an epidemiologist, spotting patterns and trends to help identify the cause of diseases, it gave him food for thought.
Working with Prof Ammar Al-Chalabi, he decided to apply a method used to help give a framework to understanding the causes of cancer to MND. “The originality of this work is not from the method itself, it comes from applying it to MND” he explained. Beginning by reminding us of work that he reported last November, he went on to describe further work in this area.
The story so far
Using a method tried and tested in cancer research Prof Pearce compared lots of sets of data from MND population registers around the world, looking at the numbers of people diagnosed with MND, and the ages they were diagnosed. He did this by plotting graphs and working out the equation of the slope of the line – it was stretching maths for first thing in the morning! This equation told him that for MND there are 6 steps to develop MND – we described this in more detail in a blog last year. One of the MND registers that was used to create this model was the South East (England) ALS Register, or SEALS. Its an example of the type of research that the currently-under-development MND Register of England Wales and Northern Ireland will contribute to in the future.
Six steps, so what are waiting for you might be thinking. But its more complicated than that (isn’t it always!). Firstly although this model suggests there are six steps, there are any number of factors that could increase the chance of a step happening. Prof Pearce used the example of smoking and lung cancer, the smoking will only be a factor increasing the likelihood of changes to cells (a step) that may in turn lead to cancer. The second point is that it won’t be the same six steps for everyone with MND (but it will be six steps).
Unravelling what the steps are
Since the research paper last year, Prof Pearce has been working to understand more about what these steps might be. This was done by adding more information about the people with MND before plotting the graphs. For example: was there a family history of MND? where in the body did the disease start? what age did the symptoms of MND start? If any of these things reduced the number of steps to develop MND, then they were candidates for being one of the steps to develop the disease.
“One of the implications of this work is that it changes the way that we think about MND. Some diseases could be described as digital and some as analogue. If this model is right, it suggests MND is digital – a series of steps that are either there or they’re not.
“ALS/MND epidemiology has been done, but not enough has been done – its why I moved into this area” he concluded.
Based on the evidence of today’s talk and the delegates reaction to it – I think he’s a very welcome addition to the MND research community!