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.