An estimated 620,000 people in the UK have a faulty gene that puts them at risk of developing coronary heart disease or sudden death, and most are unaware, a charity has warned. The British Heart Foundation said the figure was 100,000 more than had been thought and could be even higher. It said there was now a better grasp of the prevalence of inherited conditions. A child of someone with an inherited heart condition can have a 50% chance of inheriting it themselves. Each week in the UK, around twelve seemingly healthy people aged 35 or under are victims of sudden cardiac death with no explanation, largely due to undiagnosed heart conditions. Former England and Nottinghamshire cricketer James Taylor had to retire last year, at the age of 26, after he was diagnosed with the serious heart condition arrhythmogenic right ventricular cardiomyopathy.