Auckland researchers believe they have found one of the changes in the brain that results in Huntington's Disease.
Huntington's disease causes progressive breakdown of nerve cells in the brain. Photo: 123RF
It comes as British researchers announced today they've fixed a protein defect that causes the disease.
Huntington's disease is a neurological disorder that can lead to extensive loss of control over bodily movement, along with dementia, psychological disturbance and premature death.
There is no treatment, but Russell Snell of the Centre for Brain Research said they had identified raised levels of urea in the brain of a transgenic sheep model that matched human brains affected by Huntington's.
The new British findings were also promising, he said.
"What we don't know is the possibility of long-term consequences of knocking down or removing both the normal Huntington protein and the protein that carries the mutation."
Huntington's affects about one in 10,000 New Zealanders.
The New Zealand findings were published in the Proceedings of the National Academy of Sciences.
Wellington film editor Bridget Lyon was just 21 when she found out her mother had the gene for Huntington's Disease and that it had been passed down to her and her siblings.
In 2013, Lyon made the documentary The Inheritance about the toll this disease has had on three generations of her family.
She spoke to Afternoons with Jesse Mulligan about her reaction to the news of the recent breakthroughs.
Breakthrough in fight against Huntington's
'This is of groundbreaking importance'
Meanwhile, the BBC is reporting that the defect that causes the neurodegenerative disease Huntington's has been corrected in patients for the first time.
An experimental drug, injected into spinal fluid, safely lowered levels of toxic proteins in the brain, it said.
The research team, at University College London, say there is now hope the deadly disease can be stopped.
Sarah Tabrizi, the lead researcher and director of the Huntington's Disease Centre at UCL, said: "I've been seeing patients in clinic for nearly 20 years, I've seen many of my patients over that time die.
"For the first time we have the potential, we have the hope, of a therapy that one day may slow or prevent Huntington's disease.
"This is of groundbreaking importance for patients and families."
Doctors are not calling this a cure. They still need vital long-term data to show whether lowering levels of Huntington will change the course of the disease.
The animal research suggests it would. Some motor function even recovered in those experiments.
John Hardy, who was awarded the Breakthrough Prize for his work on Alzheimer's, described it as "potentially, the biggest breakthrough in neurodegenerative disease in the past 50 years".
"That sounds like hyperbole - in a year I might be embarrassed by saying that - but that's how I feel at the moment."
Giovanna Mallucci, who discovered the first chemical to prevent the death of brain tissue in any neurodegenerative disease, said the trial was a "tremendous step forward" for patients and there was now "real room for optimism".
But Professor Mallucci, who is the associate director of UK Dementia Research Institute at the University of Cambridge, cautioned it was still a big leap to expect gene-silencing to work in other neurodegenerative diseases.
"The case for these is not as clear-cut as for Huntington's disease, they are more complex and less well understood.
"But the principle that a gene, any gene affecting disease progression and susceptibility, can be safely modified in this way in humans is very exciting and builds momentum and confidence in pursuing these avenues for potential treatments," she told the BBC.
- RNZ / BBC