The CYP2A6 gene exhibits copy number variation. Individuals may carry deletion alleles or extra copies of CYP2A6. CYP2A6 SNP genotyping assays run on samples lacking CYP2A6 genes will not amplify, homozygous samples having 1 or more gene copies typically cluster together, and heterozygous samples with more than 2 copies may run between the 2 copy heterozygous and homozygous genotype clusters. In addition, some relatively rare CYP2A6 alleles contain CYP2A7 pseudogene sequences. For accurate CYP2A6 genotype analysis, copy number analysis must be done. For more information, refer to the PGx Experiments User Guide (Pub. # MAN0009612) Chapter 2 Copy Number Variation section.
For this assay, SNP(s) [rs28399435] are located under a primer sequence. To help evaluate the possible impact of a given SNP on your experiment, please refer to the
1000 Genomes and NCBI
dbSNP databases. A higher minor allele frequency in your study population represents a higher risk to assay performance. When this SNP is present, a CYP2D6*15 position sample will run between the heterozygous and wild type clusters.