With age, large arteries, which distribute blood from the heart to the result of the body, start to lose their elasticity and become stiffer. This is known as arterial stiffness. Arterial stiffness is an important risk factor for developing cardiovascular disease for which there is currently no treatment. We know that arterial stiffness is a heritable trait. This means that variation in arterial stiffness between individuals is in part due to their genes. But it is not well understood what genes are responsible for arterial stiffening. The aim of this study is to use measures of arterial stiffness called distensibility, which have already been taken in the UK Biobank cohort, to confirm they are a risk factor for development of cardiovascular disease and to investigate which genetic variants associated with distensibility. This would give us insight into the mechanisms which may underlie stiffening of large arteries and potentially identify targets for treatment of arterial stiffness.