Hyperlipidemia is a condition associated with an increase in triglycerides and cholesterol and reduced levels of high density lipoproteins (HDL) in the blood. While lifestyle choices influence the levels of cholesterol and triglycerides, familial hypercholesterolemia and hypertriglyceridemia can be passed down generations.
Hyperlipidemia is an asymptomatic disease and only way the common ways detect is blood test for lipid profile. Alterations in genes (e.g. ABCA, APOA1, APOA5, APOB, APOC2, APOC3, APOE, LDLR, LIPA, PCSK9 etc.; see gene panel below) can alter lipid metabolism and increase the risk of developing hyperlipidemia. These alterations can be inherited over successive generations also. Undetected, it can leads to serious complications like heart attack, stroke, renal failure, myopathies, liver diseases or peripheral artery complications (e.g. Raynaud’s disease etc.). These can occur when high cholesterol has led to plaque buildup in your arteries that limits or blocks the flow of blood.
There are different forms of hyperlipidemia i.e Familial cholesterolemia, hypertriglyceridemia and mixed hyperlipidemia. A blood based examination can tell the levels of Total cholesterol, Low-density lipoprotein (LDL) cholesterol, High-density lipoprotein (HDL) cholesterol and Triglycerides. However, it would not be able to identify those at risk of having abnormal lipid profiles due to familial or lifestyle choices.
Familial hypercholesterolemia (caused by alterations in LDLR, APOB, PCSK9 or LDLRAP1 genes) is an inherited condition characterized by very high levels of cholesterol in the blood. Genetic alterations can be passed down generations and early detection can help reduce risk through appropriate life style choices. Familial type 1 hyperlipoproteinemia (LPL alteration causing deficiency of lipoprotein lipase enzyme) is another inherited lipidemia, which is distinct from other hyperlipidemias. It usually presents in childhood as severe hypertriglyceridemia, episodic abdominal pain, recurrent acute pancreatitis, xanthomas and extensive chylomicrons in urine.