Screen for genetic susceptibility to non-alcoholic fatty liver disease and cirrhosis progression in alcoholic liver disease.
Polymerase Chain Reaction/Fluorescence Monitoring
Transport 3 mL whole blood. (Min: 1 mL)
Plasma or serum. Specimens collected in sodium heparin or lithium heparin
Ambient: 72 hours; Refrigerated: 1 week; Frozen: unacceptable
Background Information for Non-Alcoholic Fatty Liver Disease Susceptibility (PNPLA3) Genotyping:
Characteristics: Fatty liver disease is the accumulation of excessive triglycerides in the liver that may cause an inflammatory response, which can progress to fibrosis, cirrhosis, and liver cancer. The c.444C>G; p.I148M variant in the PNPLA3 gene confers an increased risk for the onset and progression of non-alcoholic fatty liver disease (NAFLD). This allele also confers an increased risk for the onset and progression of cirrhosis among individuals with alcoholic liver disease.
Incidence: NAFLD occurs in approximately 20-30 percent of individuals in the US.
G Allele Frequency: Varies by ethnicity; Latino 0.57, East Asian 0.38, European 0.23, South Asian 0.22, Africans 0.14.
Cause: Risk factors for non-alcoholic fatty liver disease include obesity, diabetes, insulin resistance and genetic risk factors including PNPLA3 c.444C>G; p.I148M.
Clinical Sensitivity: Unknown.
Variant Tested: PNPLA3 c.444C>G; p.I148M (rs738409).
Methodology: Polymerase chain reaction followed by high-resolution melt analysis.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Only the c.444C>G; p.I148M variant in the PNPLA3 gene will be targeted. Diagnostic errors can occur due to rare sequence variations.
Laboratory Developed Test (LDT)
|Component Test Code*||Component Chart Name||LOINC|
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