Genetics and rare diseases
Genetics and rare diseases
Kathryn North has a fascination for solving problems and particularly loves a good cryptic crossword. It’s no surprise then that the dynamic leader of the Murdoch Children's has devoted her life to finding solutions for some of the more unusual disorders affecting children.
From investigating birth defects caused by thalidomide to researching neurofibromatosis and muscular dystrophies – and treating children with these conditions – Kathryn’s interest has always been piqued by the rarer diseases.
It’s perhaps fitting that she finds herself at the helm of the Murdoch Children's, an Institute founded 30 years ago by Professor David Danks, a man who shared her intrigue for rare disorders.
Kathryn’s enthusiasm for research was sparked during her medical degree when she took a year off to research birth defects linked to thalidomide. During her paediatric training she found another passion – working with children.
“In paediatrics, kids are open books,” she smiles. “As soon as they’re feeling better, they’re up and about. I love children, just dealing with them. You can love your patients. You can give them a cuddle. When you work with them over many years, as I do, you become part of their families.”
Kathryn’s own family – she is the youngest of four children – was an even earlier influence on her career. Her father was diagnosed with stomach cancer when she was just 12 and he passed away two years later. It was a very early exposure to the medical world for the young Kathryn, but it had a lasting impact.
Her mother, who had given up work to raise her children, returned to the workforce after her husband’s death. She encouraged her children, especially the girls, to do well.
“She was determined that her daughters would get a good education. She went back to work to make sure I could go to university,” Kathryn says.
She paid tribute to her mum in a recent Mother’s Day magazine special. “My mother was a force in my life,” she told the Australian Women’s Weekly. “A fierce advocate of equal opportunity, she drilled into me from an early age that I could achieve anything I put my mind to.”
Guided by her lifelong mentor, Professor Robert Ouvrier – “he’s like my medical dad” – Kathryn trained as a paediatrician and neurologist, then undertook her doctorate on neurofibromatosis. The condition, which came to fame as the ‘Elephant Man’ disease, affects one in 3,000 people.
During her doctorate Kathryn established a clinic to look after patients with neurofibromatosis. The demand was astonishing – the clinic saw more than 200 patients in the first six months. It became obvious that many of these children were experiencing learning difficulties and she began to study why – research she continues to this day.
Her foray into muscular dystrophies began in the United States, where she snared a job in the Harvard Genetics Program, based at the Boston Children’s Hospital. She worked in the lab of Dr Louis Kunkel, who identified the dystrophin gene which causes Duchenne and Becker muscular dystrophy.
Kathryn is internationally recognised for the discovery of the gene ACTN3, which she initially thought may be linked to muscular dystrophy. She identified a change in the gene that stops the ACTN3 protein from being expressed in skeletal muscle – but rather than causing disease, it is a normal variant, occurring in one in five Australians and more than 1.5 billion people worldwide. Her studies in elite athletes have demonstrated that ACTN3 is a major determinant of skeletal muscle performance. Dubbed the “gene for speed”, it was found in the majority of elite sprint athletes but is not necessary for endurance performance. Kathryn’s team recently proved that variations in ACTN3 influence disease severity and progression in Duchenne muscular dystrophy. They are now studying how it influences muscle-wasting associated with age and cancer.
Perplexed as to why it was so common, Kathryn delved deeper and traced its origins back to evolution. It became more widespread when man migrated out of Africa during the last Ice Age, says Kathryn. Without ACTN3, people have slower glucose metabolism so they use energy from food more effectively. Their bodies are also more efficiently equipped to generate heat in the cold. “Not having ACTN3 became so common because it gave you a survival advantage during times of famine and cold in the Ice Age,” Kathryn says. But in modern times with sugar-laden diets, it may well be linked to increased risk of diabetes and obesity.
In 2012, Kathryn was awarded a Member of the Order of Australia (AM) for service to medicine in the field of neuromuscular and neurogenetics research, paediatrics and child health.
After three decades in Sydney (apart from her stint in Boston), Kathryn was drawn to the Murdoch Children's in 2013. It was a big move. The attraction was the integration of research with The Royal Children’s Hospital in a purpose-built facility alongside the University of Melbourne and the Victorian Clinical Genetic Service, providing a unique opportunity to translate the latest discoveries into clinical practice. In a short time, she has established a clinical trials centre and placed the Institute at the forefront of the genomics revolution. Advances in genetic technology mean all genes can now be sequenced quickly and cheaply, and the information used to predict, diagnose and treat rare diseases and inherited forms of cancer.
Kathryn envisions a future where genes for more complex disorders including mental health disorders, diabetes and cardiovascular disease could also be identified, and the newborn heel-prick test screens for thousands of disorders. Kathryn and Deputy Director Andrew Sinclair lead the Australian Genomics Health Alliance, working towards integrating genomics into healthcare nationwide.
“This is an ambitious goal,” Kathryn says. “But this place has just got the feeling that you can make anything happen.”