How do you inherit familial hypercholesterolemia?
FH is an inherited condition and can be passed on through your family. If one of your parents has FH then there’s a 50% (or 1 in 2) chance that you could inherit it. If you do, then there’s also a 50% chance you could pass it on to each of your own children.
It’s in the genes
Simply put, it’s caused by inheriting a gene that has a mistake in it.
Hereditary genetic disorders are passed down through a family – FH is a dominant genetic disorder, which means only one parent needs to pass the mutated gene down.
The abnormal gene is dominant. This means children who have one parent with FH have a 50% chance of inheriting the condition, known as heterozygous FH (HeFH).
If a child inherits the gene, because it is dominant, he or she will have the disorder. This means even if a child receives a healthy gene from the second parent, the altered gene will cancel out the healthy one.
According to the National Institutes of Health , people with heterozygous FH typically have an LDL cholesterol level two to three times higher than normal.
If both parents have FH, there is a 25% chance that each child will inherit the FH gene from both of them. If the child inherits the FH gene from each of them, they then have two FH genes and this is called homozygous FH (HoFH).
Having two FH genes makes the disorder much more severe. Homozygous FH is very rare. Homozygous FH means extremely high levels of LDL cholesterol and symptoms can be seen in childhood. Homozygous FH is much more difficult to treat adequately and people with homozygous FH can suffer from cardiac health issues even before the teen years.