A rare, inherited condition causes dangerously high cholesterol, even in newborn babies.

But if you have it, you probably have no idea.

A new Mayo Clinic study has found that current genetic screening guidelines fail to detect nearly 90% of those who have familial hypercholesterolemia [hi-per-cholester-o-lee-me-uh].

The condition is one of the most common genetic disorders and affects an estimated 1 in 200 to 250 people around the world.

It leads to extremely high levels of low-density lipoprotein, or LDL cholesterol, often referred to as the bad cholesterol.

The disorder snakes its way through family lines for years. It can be effectively treated with lifestyle changes and medication, but 9 in 10 of those who have it are unaware. Not knowing the condition needs treatment is dangerous, leaving the undiagnosed at risk for heart attacks and strokes.

In the Mayo Clinic study, researchers used exome sequencing to examine the protein-coding sections of the genome, which is where most disease-causing mutations happen. More than 84,000 participants in Arizona, Florida and Minnesota were screened and 419 people with familial hypercholesterolemia were identified.

Nearly 75% of those would not have met existing guidelines for testing based on their cholesterol levels or reported family history.

Researchers said expanding routine screening could help detect most people living with the genetic condition, reducing the likelihood of poor outcomes. They said the findings underscore the need for genomics-driven health care.

It stands to reason:  You can’t fix a problem if you don’t know it exists.