Ordering Recommendation

Screen for genetic susceptibility to non-alcoholic fatty liver disease and cirrhosis progression in alcoholic liver disease.

Mnemonic

PNPLA3

Methodology

Polymerase Chain Reaction/Fluorescence Monitoring

Performed

Sun-Sat

Reported

7-10 days

New York DOH Approval Status

Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.

Specimen Required

Patient Preparation
Collect

Lavender (EDTA).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Plasma or serum. Specimens collected in sodium heparin or lithium heparin

Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: unacceptable

Reference Interval

Interpretive Data

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.
Inheritance: Multifactorial.
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. 

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Compliance Category

Laboratory Developed Test (LDT)

Note

Hotline History

N/A

CPT Codes

81479

Components

Component Test Code* Component Chart Name LOINC
2014600 PNPLA3 Specimen 31208-2
2014601 PNPLA3 Variant 35474-6
2014602 PNPLA3 Interpretation 50398-7
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • Hepatic steatosis genotyping
Non-Alcoholic Fatty Liver Disease Susceptibility (PNPLA3) Genotyping