TGFB1 Polymorphism Real-Time PCR Genotyping for Radiation-Induced Fibrosis
Qualitative Real-time PCR
Indication
TaqManTM based polymerase chain reaction (PCR) to determine the genotype for a single nucleotide polymorphism (SNP) of transforming growth factor beta1 (TGFB1) C-509T (rs1800469) polymorphism located on chromosome 19:41354391 (GRCh38.p12) in patients who plan to receive radiotherapy after breast cancer surgery to predict the relative risk for developing breast fibrosis. The rs1800469 SNP refers to presence of Thymine (T) corresponding to the reference allele, and/or Cytosine (C) corresponding to the alternate allele, in TGFB1 promoter.
Methodology
DNA extracted from white blood cells in peripheral blood, or other sources (e.g., saliva) are analyzed through a qPCR reaction using allele-specific Taqman™ probes, with genotypes called with Taqman™ Genotyper software V1.4.0 (ThermoFisher Scientific). This test is designed to determine the genotype of the TGFB1 rs1800469 polymorphism as CC, CT or TT. This is a qualitative assay with 100% analytical specificity. The LOD for this was established at 5 ng DNA input, and the reference panel is created with cell lines and previously analyzed patient samples with known genotypes.
Test Parameters
The assay is validated for use in germline testing using a peripheral blood sample. The assay is not validated for FFPE samples. The assay is validated for use in pre-transplant setting only. Genotyping of host DNA in the presence of multiple genomes (granulocyte transfusion, stem cell transplant) is not supported and may likely be non-informative. Correlation with any history of granulocyte transfusion and stem cell transplant is recommended. The genotype may be affected by loss/gain of one or both TGBF1 rs1800469 alleles on
Analytical Specificity is 100% correlated to Sanger sequencing-based genotyping.
Turnaround Time
Five to 10 working days
Sample Requirements
- 10 ml peripheral blood in purple top tube (EDTA Vacutainer), sent by overnight express mail on wet ice
CPT Codes
81479
The CPT codes provided 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 payer being billed.