- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: AMD is a degenerative disease of the retina that results in progressive loss of central vision; it is the most common cause of irreversible vision loss in the Western world. Dry AMD (90 percent of cases) is characterized by the presence of extracellular deposits called drusen; wet AMD (10 percent of cases) is associated with neovascularization of the choroid.
Prevalence: 1.6 percent at 52-64 years, 11 percent at 65-74 years and 28 percent at>74 years.
Risk Factors: Cigarette smoking, increasing age, BMI>24, dietary fat intake, Caucasian ethnicity, female gender and genetic mutations (below).
Mutations Tested: A69S (c.205G>T) in the ARMS2 gene (also known as LOC387715) (Age-related maculopathy susceptibility 2) and Y402H (c.1277T>C) in the CFH gene, encoding complement factor H. These mutations are associated with approximately 70 percent of the risk of AMD.
Clinical Sensitivity & Specificity: Unknown.
Methods: Polymerase chain reaction and fluorescence monitoring.
Analytical Sensitivity & Specificity: 99 percent.
Limitations: Mutations other than those targeted will not be detected. Diagnostic errors can occur due to rare sequence variations. The mutations tested are associated with risk of AMD; they may not be causal for the disorder.
This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.
|Component Test Code*||Component Chart Name||LOINC|
|0051675||Macular Degeneration - Y402H Variant|
|0051676||Macular Degeneration - A69S Variant|
|0051677||Macular Degeneration Interpretation|
|2001295||Macular Degeneration - Specimen|
- Macular degeneration molecular assay