Detection of rare variants in backgrounds with large amounts of wild type DNA (like somatic mutations, SMs, or Non Invasive Prenatal tests, NIPTs) is often challenging. PentaBase has introduced BaseBlockers™ to improve the detection of rare variants. BaseBlockers™ are based on PentaBase’s proprietary DNA analogue platform technology and ensure a highly sensitive detection of rare mutations in backgrounds of wild type DNA from small DNA samples. The BaseBlocker™ sequence binds specifically to the wild type DNA region and blocks amplification of wild type DNA during PCR while only allowing amplification of mutant DNA. In this way the rare variant DNA is selectively amplified. Such amplification can either be followed during selective amplification in for example a real-time PCR instrument or it can be detected post amplification using various techniques like next generation sequencing or enzymatic reactions.