Genetic testing can be important in screening, diagnosis, and potentially in treatment of lipid disorders, particularly for familial hypercholesterolemia (FH), familial chylomicronemia syndrome (FCS) and sitosterolemia. FCSNext: Familial chylomicronemia syndrome is a rare genetic disease characterized by the build up of chylomicrons (chylomicronemia), the largest lipoprotein particle, which are responsible for transporting dietary fat and cholesterol. FCS occurs in approximately 1 in 1,000,000 individuals worldwide and is characterized by recurrent pancreatitis and severe hypertryglyceridemia (leading to eruptive xanthomas and lactescence of the plasma). Due to the rarity of the condition, the clinical progression of FCS is not well understood.  FCS may also be underdiagnosed, as high levels of triglycerides may be attributed to other causes before a proper diagnosis is made.  Most cases present in in childhood or adolescence; however, patients can present in adulthood.  FCS is inherited in an autosomal recessive manner. The FCSNext test is a 5 gene panel that analyzes genes most commonly associated with FCS. The test can be an effective way of identifying at-risk individuals or confirming a diagnosis. This allows for better individualized disease management and treatment decisions. Sitosterolemia: Sitosterolemia is a rare autosomal recessively inherited lipid metabolic disorder that can lead to an increased risk of coronary artery disease and heart attack. Sitosterolemia occurs in approximately 1 in 50,000 individuals worldwide. Sitosterolemia patients develop hypercholesterolemia, tendon and tuberous xanthomas, premature development of atherosclerosis, and abnormal hematologic and liver function test results. The majority of patients are diagnosed in childhood. Our sitosterolemia test is a 2 gene panel that analyzes genes most commonly associated with sitosterolemia. The test can be an effective way of identifying at-risk individuals or confirming a diagnosis. This allows for better individualized disease management and treatment decisions.   There is also an option to choose from an 18 gene lipid menu to customize a test using our supplemental order form. This customizable form will give you the ability to test for the following rare lipid disorders: Familial HDL deficiency Lysosomal acid lipase deficiency LCAT deficiency/Fish-eye disease Hyperlipoproteinemia type III Cerebrotendinous xanthomastosis (CTX) Apolipoprotein C-III deficiency

Knowing if your patient has a lipid disorder can help you determine their future coronary artery disease risk and guide your medical management recommendations. Key benefits include:

1. Confirm a diagnosis, particularly when clinical criteria are unclear or borderline in an individual
2. Help tailor medical treatment
3. Clarify risks to family members, including the inheritance pattern

• Genetic testing for FCS is recommended when patient has:¹
  • TG/TC ratio > 5 mg/dL
  • History of pancreatitis
  • Symptoms < 40y
• Genetic testing for sitosterolemia is recommended when patient exhibits these symptoms:
  • Tendon and tuberous xanthomas (build-up of yellowish cholesterol rich material over joints)
  • Hemolysis (destruction of red blood cells) and platelet abnormalities
  • Early coronary atherosclerosis due to plaque and fat build up
  • Some patients have high cholesterol with no family history of it