Mysteries of the Mind

How researching Huntington's Disease is also helping us to grasp the incredible scale of complexity of the human brain.

Next, I speak with Professor Richard Faull who set up this Brain Research Centre at Auckland University to find out how researching Huntington's disease is also helping us to grasp the incredible scale of complexity of the human brain.

Richard -   So, Huntington's disease was certainly thought to be a simple disease because it was caused by one gene and why there has been so much attention on this gene scientifically and on this disease, was a simple idea.  If we could solve this disease by working out what this one gene defect caused, then we could solve diseases like Alzheimer's, Parkinson's, and motor neuron disease which are multiple gene diseases.  Well, it just so happens that we now know that this single-gene disease, Huntington's disease is a very complicated disease because it actually causes dysregulation and upset of at least a quarter of all the genes. 

We have 45,000 genes in each cell and depending on what part of the brain it is, will upset different combinations of these other genes you see.  That's why you get all the different symptoms.  And so, genetics is a very complex science now.  We thought it was a simple science when I was at school and that this gene would do just one thing.  It doesn't.  The gene makes a protein, that protein interacts with other genes, and causes them to change their function or change their pattern of protein production.  So, there is a sort of an effect which spreads like wild fire in variable ways.  And the variation is affected by the environment.  And so, we know that people in different environments, even with the same gene will result in different patterns of brain degeneration symptoms.  And Huntington's disease has taught us the fundamental principles that the human brain is more complex than what we ever, ever imagined. 

We can't explain a human thought.  We can't explain why the sudden burst of genius, and we're beginning to unravel it.  But it's almost as if we climb to the top of Mt. Everest, thinking we're going to solve this disease and then we see all the Himalayas before us which are even higher.  And that's the challenge of doing brain research.  it's going to be several lifetimes of work to unravel a human brain.  And this disease has actually led us along that path.

Hannah -   Thanks to Richard Faull