People with heart disease have higher levels of PCSK9 in their blood, and that’s linked to higher activity of inflammation proteins in their immune cells — even when their cholesterol is low from taking statins.

People born with a certain gene change that breaks the PCSK9 gene tend to have much lower 'bad' cholesterol their whole lives and are far less likely to get heart disease — so scientists think blocking this gene with medicine might help protect others' hearts too.

PCSK9 doesn't just raise bad cholesterol — it also directly worsens artery disease by making immune and blood vessel cells absorb more damaged fats, reducing their ability to clean out cholesterol, and increasing inflammation in the arteries.

People with certain genetic changes that turn down a protein called PCSK9 tend to have lower 'bad' cholesterol their whole lives and are much less likely to get heart disease.

Some cholesterol-lowering drugs called PCSK9 inhibitors can lower a specific type of blood fat linked to heart disease, and that might help protect people with high levels, but scientists aren't sure exactly how it works yet.

People who naturally have a broken PCSK9 gene — which keeps their bad cholesterol low their whole life — are much less likely to get heart disease, and this seems to be true for people of many different backgrounds.