Apolipoprotein L1 (APOL1) Renal Risk Variant Genotyping

Test Code

1291

CPT Codes
0355U

Physician Attestation of Informed Consent

This germline genetic test requires physician attestation that patient consent has been received if ordering medical facility is located in AK, DE, FL, GA, IA, MA, MN, NV, NJ, NY, OR, SD or VT or test is performed in MA.

Preferred Specimen

4 mL whole blood collected in EDTA (lavender-top) tube, or
Pediatric (0-3 years): 2 mL whole blood collected in EDTA (lavender-top) tube

Minimum Volume

2 mL whole blood • 1 mL pediatric

Other Acceptable Specimens

Saliva collected using Oragene OGD 500 saliva collection kit (Follow manufacturer's instructions)

Instructions

Please label each specimen tube with two forms of patient identification. These forms of identification must also appear on the requisition form.

Transport Temperature

Room temperature

Specimen Stability

Whole blood
Room temperature: 10 days
Refrigerated: 10 days
Frozen: Unacceptable

Saliva
Room temperature: 1 year
Refrigerated: Unacceptable
Frozen: Unacceptable

Methodology
Sanger Sequencing

FDA Status
This test was developed and its analytical performance characteristics have been determined by Athena Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: As needed; Report available: 7-10 days

Reference Range

See Laboratory Report

Clinical Significance

Two apolipoprotein L1 gene (APOL1) risk variants (referred to as G1 and G2), found predominantly in African Americans, markedly increase an individual's risk for kidney disease. The presence of two APOL1 high risk alleles (G1/G1, G2/G2, G1/G2 genotypes) confirm that the patient is at increased risk for developing focal segmental glomerulosclerosis, HIV-associated nephropathy, and hypertension attributed end-stage renal disease. Clinical studies suggest that transplanted kidneys from deceased donors with two APOL1 risk alleles have shorter graft survival than donor kidneys with zero or one APOL1 risk alleles (G0/G0, G0/G1, G0/G2 genotypes). The risk of the two APOL1 high risk alleles (G1/G1, G2/G2, G1/G2) in living kidney donors remains unknown at this time. This new test for renal transplant evaluation can serve as a companion test for the nephrology genetic panel for potential donors from the African American population. If clinically indicated, potential donors and/or recipients of all ethnic groups can also be tested with our nephrology genetics panel(s) to screen for a long list of nephrology genetic diseases. With better access to genetic information, physicians will be able to help guide donors and recipients in decisions regarding transplantation.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.