He has Sargardt's disease, which is a hereditary condition.

BBC: London 2012 NI olympians dreaming of gold

Among them are hypertrophic cardiomyopathy (HCM) - a hereditary condition in which there is excessive thickening in the heart muscle, myocarditis, which leads to inflammation of the heart muscle and coronary artery disease.

BBC: NEWS | Health | A matter of young life and death

In tackling tuberous sclerosis, the hereditary condition in which benign tumors grow in the skin, kidneys or brain, Novartis hopes a pill can improve on current treatment, which includes the surgical removal of tumors.

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