Test Details
4q25 Atrial Fibrillation Risk Genotype Test
This test identifies individuals with an increased risk of atrial fibrillation (AF) and stroke.
The 4q25 gene locus is on chromosome 4, adjacent to the PITX2 gene, which is a transcription factor required for cardiac development and left-right asymmetry of the heart, and for normal sinus node formation. Two 4q25 variants rs2200733 and rs10033464, found in about 20% of the population, have been associated with a significant 1.4-1.5 fold increased risk of atrial fibrillation (4). This association has been observed in multiple studies, and is especially apparent in subjects over age 60 years.
Reference:
- Gudbjartsson DF, Arnar DO, Helgadottir A, et al. Variants conferring risk of atrial fibrillation on chromosome 4q25. Nature. 2007;448:353-357.
Methodology
Real time polymerase chain reaction (PCR)
Patient Preparation
None
Preferred Specimen
1.0 mL whole blood collected in EDTA (Lavender Top)
Alternate Specimen
- Buccal swab
- Dried Blood collected on an AdvanceDx 100 card
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
Refrigerated: 14 days
Lab Values
4q25 Atrial Fibrillation Risk Genotype Test
rs2200733
- Optimal
- Genotype C/C
- Borderline
- Genotype T/C
- Genotype T/T
rs10033464
- Optimal
- Genotype G/G
- Borderline
- Genotype T/G
- Genotype T/T
Clinical Significance
4q25 Atrial Fibrillation Risk Genotype Test
rs2200733
- Normal risk of atrial fibrillation (AF) and stroke
- Genotype C/C
- 1.5-fold increased risk of atrial fibrillation (AF) and stroke
- Genotype T/C
- Genotype T/T
rs10033464
- Normal risk of atrial fibrillation (AF) and stroke
- Genotype G/G
- 1.4-fold increased risk of atrial fibrillation (AF) and stroke
- Genotype T/G
- Genotype T/T
Treatment Options
4q25 Atrial Fibrillation Risk Genotype Test
rs2200733
- Monitor for AF and if it develops, use anticoagulant therapy
- Genotype T/C
- Genotype T/T
rs10033464
- Monitor for AF and if it develops, use anticoagulant therapy
- Genotype T/G
- Genotype T/T
