Fifty years after South Africa performed the world's first successful heart transplant, a woman from the Cape Flats has made another landmark medical discovery that could prevent hundreds of cardiac-related deaths every year.

The discovery of a gene that is a major cause of sudden death among under-35s is likely to put South Africa on the map in the world of genetics, showing that the country "is on par with international researchers".

Maryam Fish, 30, of Lansdowne, led an all-female team of researchers at the University of Cape Town (UCT), along with Gasnat Shaboodien and Sarah Krause, who made the discovery with researchers from Italy.

The gene, called CDH2, is found in everyone, but a mutation causes a genetic disorder known as arrythmogenic right ventricle cardiomyopathy (ARVC), which increases the risk of heart disease and cardiac arrest. Sudden cardiac death is estimated to hit more than five young people in South Africa daily, according to the Medical Research Council.

In under-35s, an inherited form of disease of the heart muscle plays a prominent role in fatalities as a result of cardiac arrest. "We sequenced all the genes in the human genome in two cousins who were affected," said Fish, explaining that the cousins were identified after a 22-year-old relative died suddenly.

"We then looked for common variants and had a list of 13 000, which we narrowed down through a series of filtering criteria until we got the CDH2 variant, which was the most likely causal variant in this family."

The team then screened the gene in a number of unrelated individuals who also had ARVC. This added "more evidence to our case that the CDH2 gene was the causal gene for ARVC". Announcing the discovery recently, UCT Dean of Health, Bongani Mayosi, likened its importance to the first heart transplant, performed by Dr Christiaan Barnard at Groote Schuur Hospital in Cape Town in 1967. – Source: www.timeslive.co.za