Identifying a Genetic Basis of Multiple Sclerosis
Multiple sclerosis (MS) is a progressive disease affecting the central nervous system. The myelin sheath encompassing nerve fibres is destroyed, resulting in a loss of neuronal function. It tends to occur in circumscribed areas, causing a specific neurological deficit and a focal "patch" that can be seen on MRI scans of the brain. MS has several different forms. The most common is the relapsing remitting variety where patients experience worsening of symptoms followed by full to partial recovery. Unfortunately for most patients the course for this variety is progressively downwards. Primary progressive MS has no such variation and there is a steady decline in function.
MS is more common in Tasmania than other states and there appears to be a latitudinal gradient which may be explained by a decreasing exposure to sunlight. However, there is definitely a significant genetic component to MS with siblings of affected individuals having a 40-fold higher risk of contracting the disease than others in the population. We know the MHC region of the genome contributes significantly to disease with the DR15 haplotype being enriched in MS patients. This does not explain all the genetic contribution to disease. There are likely to be many more loci involved. We are trying to find these loci.
We have been working on this for a number of years and up until recently the technology has not been sufficiently sensitive to identify these genes. We can now survey the entire genome with high density arrays. This has recently been done as a consortium of most MS researchers in Australia with some interesting results emerging.
We are following up some of these results.
This project requires sophisticated statistical analysis, high throughput genotyping and careful clinical analysis.
- Professor Simon Foote
- Dr Brendan McMorran (Member)
- Associate Professor Joanne Dickinson (Member)
- Professor Bruce Taylor