Overview: PAI-1 4G-5G Genotyping TestIntroduction: The PAI-1 4G-5G Genotyping Test detects PAI-1 gene mutations to diagnose clotting risk, causing thrombosis. Following 2023 ISTH guidelines, it uses PCR for high specificity, supporting genetic screening. This test is critical for guiding risk assessment, treatment planning, and improving outcomes in molecular pathology for patients with suspected thrombophilia.
Other Names: PAI-1 Genotyping Assay, 4G/5G Polymorphism Test.
FDA Status: Laboratory-developed test (LDT), meeting molecular pathology standards for diagnostic accuracy.
Historical Milestone: PAI-1 genotyping began in the 1990s with thrombosis genetic research. PCR methods improved in the 2000s, enhancing diagnostic precision.
Purpose: Detects PAI-1 4G/5G mutations to diagnose clotting risk, guides treatment, and evaluates patients with thrombosis.
Test Parameters: 1. PAI-1 4G/5G Genotype
Pretest Condition: No fasting required. Collect whole blood, buccal swab, or saliva. Report history of thrombosis or family clotting disorders.
Specimen: Whole Blood (EDTA, 2-5 mL), Buccal Swab (sterile swab, 1-2 swabs), Saliva (sterile container, 1-2 mL). Transport in a biohazard container.
Sample Stability at Room Temperature: 24 hours
Sample Stability at Refrigeration: 48 hours
Sample Stability at Frozen: Not frozen
Medical History: Document thrombosis, family history of clotting disorders, or cardiovascular events. Include current medications, especially anticoagulants.
Consent: Written consent required, detailing the tests purpose, clotting risk implications, and risks of sample collection.
Procedural Considerations: Uses PCR to detect PAI-1 4G/5G polymorphisms. Results are available in 3-5 days, supporting clinical decisions. Performed in laboratories, often for genetic clotting risk assessment.
Factors Affecting Result Accuracy: Low DNA yield or improper sample storage can affect results. Contamination may reduce specificity.
Clinical Significance: 4G/4G genotype confirms increased clotting risk, guiding anticoagulant prophylaxis. 5G/5G may indicate lower risk, requiring clinical correlation.
Specialist Consultation: Consult a hematologist or geneticist for result interpretation and treatment planning.
Additional Supporting Tests: PAI-1 antigen levels, D-dimer, or other thrombophilia genetic tests to confirm clotting risk.
Test Limitations: Genotype alone does not predict thrombosis; clinical correlation is needed. Sample quality affects sensitivity.
References: ISTH Thrombophilia Guidelines, 2023; Journal of Thrombosis and Haemostasis, Eriksson P, 2022.
