Huntington's disease

Today I'm going to talk about Huntington's disease. My name's Roger Barker, I'm a consultant neurologist at the Addenbrooke's Hospital in Cambridge in the United Kingdom, as well as the Professor of Clinical Neuroscience. I look after patients with Huntington's disease, and we also do research both within the lab and in the clinic into this condition. In this topic, I'm going to take through a little of the background of Huntington's disease, and then talk a little bit about certain aspects of it. I hope this will help you to understand a bit more what this condition entails, and some of the new developments which have happened more recently, in terms of our understanding of both how it expresses itself in the clinic and some of the new treatments.

Huntington's disease takes its name from George Huntington who described the condition in 1872. It wasn't until 1983 that the genetic link to chromosome 4 was discovered, and in 1993 the gene itself was found which codes for huntingtin protein. It's an autosomal dominant condition, and the abnormal gene codes for an abnormal form of the huntingtin protein (htt). Autosomal dominant means that if you inherit one abnormal gene, then you will definitely get the condition. For most people with Huntington's disease they present between the ages of 30 and 50, but it can present at any age. There are people who present under the age of 21 who are said to have 'juvenile Huntington's disease'. There are people who have late-onset Huntington's disease, the age for which is a bit variable, but most people would say it's over the age of 60 or 70. Certainly, my experience has been in recent years that we're seeing more people presenting later in life with the first manifestations of this condition. Once it develops (or becomes clinically manifest) it progresses over 20 years, and most patients will sadly die of this condition rather than with it. It's a relatively rare condition, in the United Kingdom there are between 5,000 and 6,000 thousand cases, in comparison there are 130,000 cases of Parkinson's disease, and over half a million people with Alzheimer's disease. So it's a rare condition, it is a genetic disorder for which we know the gene and we can test patients. It does have special prominence in the world of research around neurodegeneration. In my part of the world in Cambridge, there is a town up the A14 called Huntingdon. The disease is often referred to as that by many physicians, which is incorrect because (as I said) it takes its name from George Huntington. We've also moved away from calling it Huntington's 'chorea', which is the movement disorder associated with it, to emphasize that the disorder is much more disseminated in terms of its clinical features as well as its pathology. We refer to it as Huntington's disease. As with all diseases we often try and find someone famous who's had this condition, but we slightly struggle with Huntington's disease. It is described in Ian McEwan's novel 'Saturday' where one of the main protagonists has this condition. Probably the most famous version is Woody Guthrie, that most people will never have heard of. He was a folk musician in the United States in the mid-part of the last century. The Guthrie Foundation was set up in memory of him, that then led to the registry of the disease foundation, and that in turn led to the discovery of the gene. From Woody Guthrie, major research and discoveries have been made in this condition.