- Patient Preparation
- Lavender (EDTA) or pink (K2EDTA)
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: 1 month
Characteristics: Lower sensitivity to opioid receptor agonists prescribed for pain control (e.g., morphine) and higher sensitivity to opioid receptor antagonists used in the treatment of alcohol and opioid dependency (e.g., naltrexone).
Inheritance: Autosomal recessive.
Cause:OPRM1 c.118A>G (p.Asn40Asp); also known as G allele.
G allele frequency: African Americans 0.04, Caucasians 0.14, Hispanics 0.24.
Penetrance: Drug dependent.
Clinical Sensitivity: Unknown.
Methodology: Polymerase Chain Reaction/High Resolution Melt Analysis.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Only the targeted OPRM1 mutation, c.118A>G, will be detected; additional mutations in OPRM1 or other genes will not be detected. Diagnostic errors can occur due to rare sequence variations. Genetic testing is not a substitute for clinical monitoring. Non-genetic factors may also affect opioid response.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2008768||OPRM1 Genotype, Specimen|
|2008769||OPRM1 Genotype, Interpretation|
- Opioid receptor sensitivity (Opioid Receptor, Mu (OPRM1) Genotype, 1 Variant)