Copy number variation is a type of structural variation that occurs when a DNA segment of 1 kb to several megabases in length is present in variable copy numbers compared to a standard reference genome.
There are different types of CNVs, from simple tandem duplications to more complex gains or losses of these sequences at multiple sites throughout the genome. These structural variants are found in all humans as well as other animals and plants.
CNVs can influence gene expression and can be associated with specific phenotypes and diseases. This variation covers approximately 12% of the human genome and includes deletions and duplications.
Check this article in which the researchers used TaqMan CNV assay to show a relation between germline E2F1 CNV and melanoma.
TaqMan Copy Number assays offer a targeted approach combining high accuracy, specificity, ease of use and sample throughput, to validate copy number changes or screen large sample sets.
TaqMan Copy Number assays are a duplex experiment using a FAM labeled target assay and a VIC labeled reference assay in the same well to quantify small fold changes. The reference assay targets a gene of known and stable copy number. For example, RNase P is often used for human samples, as it has been shown to be present and stable at 2 copies. To determine copy number, a relative quantitation analysis is performed between the unknown sample and a calibrator sample (one in which the copy number of the target gene is known). The sample is combined with both assays, master mix, and then run in the real-time PCR instrument.
Thermo Fisher Scientific offers a free software program which will analyze the exported data from a compatible instrument. The software provides statistics to help evaluate data confidence and can calculate copy number even when a calibrator sample is not used.
Gold-standard TaqMan Assay technology enables highly accurate quantitation for copy number variation.