Genetic Testing for Autosomal Dominant Hypercholesterolemia
Familial Hypercholesterolemia

December 2008
FH has been termed autosomal codominant, meaning that the condition can occur in the heterozygous or homozygous state. As many of you know, heterozygous means that the individual has a mutation on only one copy of their LDLR gene, whereas homozygous means that there are mutations in both copies of the LDLR gene.
While LDL levels can be variable, individuals with heterozygous FH generally have LDL levels greater than 200 mg/dL, while those who are homozygous have LDL levels as high as 1,000mg/dL, sometimes higher. It is important to note that the cholesterol levels rise with age, so individuals who are younger or who have less penetrant mutations, may not demonstrate such highly elevated levels of LDL.
FH is associated with premature mortality from CVD. Heterozygous FH individuals tend to have atherosclerotic lesions in their 30s and 40s which are associated with a premature coronary artery disease (CAD). Homozygous FH individuals may have lesions as early as 6 years old. MIs can occur sometimes even in the infant stage and they often have death by 20.
Familial Hypercholesterolemia |
Jump to section:
- Introduction
- Autosomal Dominant Hypercholesterolemia
- Autosomal Dominant Hypercholesterolemia
- Autosomal Dominant Hypercholesterolemia
- Familial Hypercholesterolemia
- FH-Primary Defect in LDLR
- LDLR Gene
- LDLR Gene
- Familial Defective ApoB-100
- How is ADH Diagnosed?
- Impact of Failure to Diagnose
- Why is Genetic Testing for ADH Useful?
- Statin Treatment-How Early?
- ADH-Genetic Testing Methodology
- Familial/Autosomal Dominant Hypercholesterolemia Diagnostic Algorithm
- APOB-Targeted Genotyping Performed First
- APOB Mutation-Positive
- APOB Mutation-Negative
- LDLR Sequence Mutation-Positive
- LDLR Sequence Mutation-Negative
- LDLR Large Del/Dup Mutation-Positive
- LDLR Large Del/Dup Mutation-Negative
- Summary
- Conclusion
- Questions?


