Genetic Testing for Family Heart Disease

In the world of genetics some conditions are dominant and some are recessive.

Dominant means that only one of your parents needs has to give you the gene for a condition for you to have that condition. Familial hypercholesterolemia (FH) and elevated lipoprotein(a), or Lp(a), are both dominantly inherited conditions.

Recessive means that you must get a gene from both of your parents in order to have that condition. In the case of cystic fibrosis, for example, if there are two parents who don’t have cystic fibrosis, but they both carry the recessive gene and both pass it on their child, their child will have cystic fibrosis.

Passing on FH or High Lp(a)

In the case of dominantly inherited disorders, if one person has it, each time they have a child there is a 50% chance they will pass the condition on to that child. So, if you have FH or high Lp(a), roughly half of your first-degree relatives (parents, siblings, and children) will also have FH or high Lp(a). This is why we always say:

 

“You never find a person with FH or high Lp(a) – you find a family.”

 

When someone is diagnosed with FH or high Lp(a), it is recommended that all first-degree family members are also screened as well. This process is known as Cascade Family Screening. It doesn’t stop with first degree relatives. If one of your siblings, for example, has FH or high Lp(a), it is recommended that their children are also tested, and so on. This is an effective way to protect your entire family.

Why Family Screening for FH and Lp(a) Matters

Both FH and high Lp(a) can dramatically increase the risk of early heart disease and stroke. It would make sense that when someone is diagnosed with either disorder their siblings and children would be automatically screened.

Unfortunately, in the United States there are so many variables – differing health systems, insurance companies, and families spread across the country – that family screening has not been successful.

At the Family Heart Foundation we are working to change this. We are participating in two federally funded grants around improving family screening. Over the next few years we hope that our research, advocacy, and education will drive change in this pivotal practice.