The Lifelong Burden of Homozygous Familial Hypercholesterolemia.

Homozygous familial hypercholesterolemia is caused by mutations in the low-density lipoprotein receptor gene. It is diagnosed in children or youth who present with extensive tendinous and cutaneous xanthomas and extreme elevation of low-density lipoprotein cholesterol. Untreated, premature coronary artery disease develops in the teenage years or earlier and survival to ages older than 30 years is rare.