Table 1. Genetic classification of dyslipidemia.

Classification Examples of Genetic Diseases* Genetic Defect Common Lipid Clinical Findings (Frequency) Abnormalities** Genetic defect of LPL TG levels in the 1000’s, Eruptive Type I Lipoprotein lipase deficiency gene – autosomal with as high as over xanthomas ‘Chylomicronemia recessive 10,000 mg/dl Pancreatitis syndrome’ (increased Genetic defect triglyceride levels and ApoCII deficiency (1:1,000,000 for Partial genetic of ApoCII gene – chylomicron particles) either of the above) defects may have TG autosomal recessive levels > 500 mg/dL Multiple genetic defects – inheritance Polygenic hypercholesterolemia likely dependent upon LDL-C levels > 130 Increased risk of (1:20) underlying genetic mg/dL ASCVD abnormality Type IIa (increased Increased risk of Heterozygous familial LDL cholesterol levels premature ASCVD hypercholesterolemia LDL-C levels > 190 and/or particles) Dysfunction or (1:500) mg/dL absence of LDL Tendon xanthoma receptor – autosomal LDL-C levels Increased risk of Homozygous familial dominant sometimes > 350 mg/ premature ASCVD hypercholesterolemia dL, but most often 500 (1:1,000,000) - 1000 mg/dL Tendon xanthoma Type IIb (increased LDL-C levels > 160 Increased risk of Multiple genetic triglyceride levels, mg/dL ASCVD defects of various apo- and increased LDL Familial combined hyperlipidemia lipoproteins and/or LPL and VLDL cholesterol (1:50-1:200) TG levels> 300 mg/dL genes - ? autosomal levels and/or dominant particles) LDL-C > 220 mg/dL Palmar xanthomata Type III (increased TG levels > 300 mg/dL (orange triglyceride levels Genetic defect of apoE discoloration of and increased gene – autosomal skin creases, Familial dysbetalipoproteinemia intermediate-density recessive, or more tuberoeruptive (1:1000-1:5000) lipoprotein cholesterol rarely, autosomal xantomata of levels and/or dominant elbows and knees particles) Increased risk of premature ASCVD Type IV (increased TG levels > 150 mg/dL Unclear if triglyceride levels Unknown genetic increased risk of Familial hypertriglyceridemia and increased VLDL defect – autosomal ASCVD (1:50-1:100) cholesterol levels and/ dominant or particles) Eruptive Type V (increased xanthomas triglyceride levels Unknown genetic TG levels > 500 mg/dL and increased Hyperprebetalipoproteinemia (un- defect – possibly due Pancreatitis chylomicron and VLDL known frequency, very rare) to an LPL inhibitor – cholesterol levels and/ unknown inheritance LDL-C levels > 130 mg/dL Increased risk of or particles) ASCVD

LDL = low-density lipoprotein; VLDL = very low-density lipoprotein; Apo = apolipoprotein; LPL = lipoprotein lipase. *In addition to genetic causes, many of these hyperlipoproteinemias may be acquired or secondary to high carbohydrate diets, medications, and/or underlying diseases. Hence, the frequencies listed above only refer to the number of patients with the genetic abnormality specified and do not reflect the total frequency by which the types of lipid phenotypes are observed in clinical practice. ** The listed lipid values for genetic abnormalities should be considered common lipid values, intended to provide general values that might be encountered in clinical practice. These lipid values are not intended to be diagnostic. Lipid values can vary widely among individual patients with genetic abnormalities, especially when combined with secondary causes of dyslipidemia and other genetic abnormalities.