The long-awaited Gene Technology Bill has stalled because New Zealand First won’t support it as it stands. The sticking point, it seems, is releasing genetically modified plants or animals into the environment. But where does that leave contained genetic technologies that the bill also covers, such as medical research?
They are less controversial. The Green Party has said medical use is “widely supported and uncontentious”. Even GE-Free NZ could agree with them – if they were regulated, labelled and traceable, which the bill doesn’t require.
Bronwen Connor at the University of Auckland’s Centre for Brain Research says medical research is progressing well under existing rules.
Universities have worked with the Environmental Protection Authority (EPA) to demonstrate that the viruses that ferry genes into cells can be used safely.
“They’re now seen as reasonably low risk because they only affect the cell once – they’re non-replicating. We still need approval, but it’s a very low-level approval now.”
She has worked with virus-delivered gene therapies in the lab to protect brain cells ravaged by Parkinson’s and Huntington’s disease.
Clinical trials that use gene therapies in people also need approval from the EPA. “That’s still done in a very tight regulatory system,” she says. “It has to be done in a high-level manufacturing process anyway. It’s got medical requirements behind it as well.”
The same virus delivery system is the basis for other Huntington’s research, too, including the first gene therapy shown to slow the progress of the disease in a clinical trial in the UK and US by Dutch company UniQure.
Russell Snell, also of the Centre for Brain Research, is a world expert in Huntington’s genetics, and in 1993 helped discover the inherited gene mutation that causes the fatal disease. Snell says the Dutch therapy interferes with the production line that starts with the gene and ends with a protein that destroys brain cells. “The virus sits there in the brain cells and makes copies of a small RNA molecule.” That molecule is the true treatment. It binds to RNA that’s an essential step in the Huntington’s production line. The cell’s own cleaning system recognises the bound RNA as abnormal and clears it away “so the protein doesn’t get produced, or there’s a reduced amount of it. It doesn’t completely shut it off.” Patients in the trial weren’t cured, but the symptoms of those who got the highest dose progressed 75% slower than expected over the next three years. “It’s had a major beneficial effect.”
Snell says the 29 people who volunteered for the experimental treatment are heroic. Each underwent neurosurgery for 12-18 hours to infuse the treatment deep in their brain. That was even riskier than it seems, because the virus’s RNA is slightly promiscuous.
Everyone with the mutation also has a normal copy of the gene – most of us have two normal copies – which makes a helpful version of the protein. That protein is needed, at least for normal development in the womb. “The risk was that the RNA binds to both the good copy and the copy that carries the mutation, and it degrades both of them,” says Snell. “The big question was, will that cause problems? So far, it doesn’t look like it does. That’s a big deal.”
Despite the trial being small, UniQure hopes for US approval next year through an accelerated rare-disease pathway. The treatment’s invasiveness and expense – similar gene therapies cost US$2m or more – are drawbacks.
But, says Snell, “There’s a bunch of other technologies that can do that, which would hopefully be cheaper as well. This is a trailblazer study, no doubt about it. It’s told us something we’ve dreamt about for a long time.”
