Cholesterol is a type of fat made by the body. Sometimes a high level of cholesterol in the blood, also known as ′hypercholesterolaemia′, runs in families. Some families have a particular type of inherited high cholesterol caused by raised blood levels of ′low density′ cholesterol, often known as ′bad cholesterol′. This is called ′familial hypercholesterolaemia′ (or FH for short). It is not caused by an unhealthy lifestyle, but is passed from generation to generation through a ′faulty gene′. This means that brothers and sisters or children of someone with FH have a one in two (50%) chance of having the condition.

In people with FH, the raised levels of ′bad cholesterol′ lead to ′hardening′ of the arteries and an increased risk of heart disease, if left untreated. Treatment reduces the risk of heart disease and can help to ensure that people with FH have a normal life expectancy.