My early career involved working with patients with multiple sclerosis (MS) and undertaking research into how people cope with this. This experience left a lasting impression as MS is a horrible disease to live with. It is neuro-degenerative disorder resulting in progressive loss of function leading to both both physical and neuropsychological disability. There are different forms with some slow moving and some with very rapid deterioration. MS results in the destruction of the myeline in the brain. Myelin is the substance that coats and insulates brain cell in a similar way to the way that plastic coating insulates electric wiring. When the myelin is destroyed the brain short circuits. Whilst most people associate MS with older adults there is an early onset version affecting children and adolescents which is particularly devastating.

When I was working in the area a key puzzle was the geographical distribution of MS. It becomes more prevalent the further North you go. It is far more prevalent in Scotland for example, than it is in Southern Europe. Recent speculation has been that sunshine and as a result levels of vitamin D may be the reason for this geographical distribution A recent research study by Ramagopalan et al and published in PLoS Genetics has started to show in more detail the possible causal factors. They have identified a gene HLA-DRB1 that is associated with MS. More interestingly they found that vitamin D interacts with HLA-DRB1*1501 and effects whether this gene is expressed i.e the vitamin D influences whether the gene is switched on or off.

As well as identifying possible causes of MS I think this work is important as it shows the way that genes and environment can interact in neurology and neuropsychology. Genes are not totally deterministic i.e. that there is nothing you can do if you have the relevant gene. Factors in the environment can influence whether a gene is expressed. Therefore by changing the environment or behaviour we may be able to prevent genetic neurological and neurodevelopmental disorders from occurring. In the future it may be possible to screen for all genetic risk factors and then to change behaviour or take supplements to prevent neurological illness and disorder developing. In the case of MS it may be that supplementing vitamin D or exposure to sunlight for people with the deviant gene at the right critical period, can prevent the onset of MS and thus prevent a lot of distress.