Scientists have traced the cause of Kiwis who don't survive their surgery because of a fatal reaction to anaesthetics – a genetic flaw brought to New Zealand 200 years ago by one common ancestor.
Malignant hyperthermia (MH) is a genetic condition that sometimes people don't know about until it's too late, when they're in surgery. It has a particular connection to New Zealand, thanks to one family and their intriguing ancestor.
Shane Saunders of Marton is one member of that big family. He's an ex-truckie, off work at the moment because he's recovering from the amputation of his leg – a complication from a car accident years ago.
The accident meant he's had several major surgeries – bad enough for most people, but for Mr Saunders the anxiety is even higher because he has MH, and so did his mum, Gladys Ropata. She was 20 years old when she died.
"She had an appendix burst and Dad rushed her to the hospital and they gave her a general anaesthetic to operate on her and she died in theatre," says Mr Saunders.
"She wasn't tested at the time because they were unsure of it back then, but they're pretty sure now that that's what killed her [MH]."
There are around a dozen of Mr Saunders' family members who have died in the same way, from MH.
The gene traces all the way back to an immigrant called Octavius Harvey, who in 1840 sailed from Scotland via Sydney to this strange land on the other side of the world for a better life. He made his trade in the tough business of whaling.
But, most importantly, he married a local Maori woman and became the forefather of a big whanau that settled in the lower North Island, leaving around 2000 descendants and another legacy – one he would never have known about. Nine generations since him have carried MH, making Mr Saunders' the biggest family anywhere in the world with MH.
Just who does have it and who doesn't is something they can test now. Knowing before any future surgery could save lives. Doctors would be prepared for the possibility of an attack and different drugs would be used.
It's an invasive test, but it's important because of people like Mr Saunders. His daughters have a 50/50 chance of having MH. He's had two near-fatal attacks in surgery himself, and he's very aware of what he may well have passed on.
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