Identify new or novel genes which may impact on cholesterol level, and establish the relationship between those gene mutations with atherosclerosis, as well as responses to lipid-lowering drugs.

To better understand the genetics basis for LDL-C elevation and develop an optimized lipid-lowering strategy, we propose to do the following studies:

1. To establish a China HoFH registry, and collect DNA and blood samples from all available family members of each proband (pedigrees);
2. To detect gene mutations known to cause FH and identify family suitable for future whole genome sequencing aimed to identify novel genes controlling cholesterol levels.

3.To establish the relationship between types of gene mutations and lipid and atherosclerosis profile, as well as responses to lipid-lowering agents.

Inclusion criteria:

Patients of any age and sex who meet clinical or genetic criteria for hoFH as follows:

• Cutaneous xanthomata before the age of ten years
• LDLC > 13 mmol/L before treatment or > 7.76 mmol/L despite treatment
• Phenotypic features in keeping with HeFH in both parents

Exclusion criteria:

Inability of patient, or, if less than 18, a parent, to sign informed consent.

Homozygous Familial Hypercholesterolemia