Gene Research Discovery What happens when an increasing number of people with congenital heart defects are born into a society that is getting fatter and more prone to falling dead from cardiovascular disease? It would seem that we are headed towards a perfect storm of heartbreak - and a Melbourne researcher is on track to finding out for sure. The opportunity to answer this grim question arose when Dr Mauro Costa of the Australian Regenerative Medicine Institute (ARMI) at Monash University, in collaboration with the Victor Chang Cardiac Research Institute, discovered a mutation to a gene that is key to cardiac development. Because the gene occurs in every living creature that has a beating heart - from the fruit fly upward - Dr Costa has been able to produce mice with the genetic make-up of human congenital heart disease. By following the long-term effects of the genetic mutation in mice that are fattened up, Dr Costa and his team will be able to predict the fate of an ever-expanding portion of our human population. "Modern surgery is increasingly able to save babies born with heart defects," Dr Costa said. Many grow up and have babies of their own with defective hearts. The net result is "an alarming increase" in the prevalence of congenital heart disease. About 3000 people per million have congenital heart disease - and surgery is resulting in a 5 per cent increase annually in people genetically predisposed to the condition. Meanwhile, Western society is chubbing up. The combined effect of these two factors makes for a grim picture. We need to understand the interplay between lifestyle-related cardiac stress and genetic mutations so we can better manage the emerging situation," Dr Costa said. The discovered mutation affects the "tin man" gene - which technically sports the less-catchy name NKX2.5. This gene controls heart development. Dr Costa and his team discovered the defecting mutation on the gene in 2007, but the research results were only published two months ago in the American Heart Association journal Circulation: Cardiovascular Genetics. "It's early days, and it's best to keep lab results on the quiet until they're confirmed," Dr Costa said, "but so far ... well, let's just say it might pay to cut down on the cheese."