What is the main feature of branched DNA amplification (bDNA)?

Branched DNA amplification (bDNA) is characterized by its ability to amplify a signal rather than the target nucleic acid itself. The correct answer highlights that bDNA generates a signal overload, which is accomplished by connecting labeled probes that can bind to the target molecule. This method relies on the formation of branched structures of DNA that allow for multiple copies of the signal to be generated from a single target nucleic acid molecule.

In bDNA amplification, the primary process does not involve the amplification of the nucleic acid target like traditional PCR methods. Instead, it uses amplifiable probes that increase the intensity of the signal in a detectable way while avoiding the need for exponential amplification of the nucleic acid itself. This feature is key to its function in various applications, such as clinical diagnostics and gene expression studies.

Branched DNA technology includes steps where non-covalent interactions between the probes and the target do take place, and the signal is amplified by this branched architecture, leading to a detectable output without needing to amplify the target DNA sequence directly. This differentiates bDNA from other amplification techniques that rely heavily on target molecule denaturation or hybridization processes.