Which sequencing method sequences millions to billions of fragments in parallel?

• A. Sanger sequencing
• B. RT-PCR
• C. Next-generation sequencing
• D. Southern blot

Answer: (C)

Massively parallel sequencing is the method described here. It sequences millions to billions of DNA fragments at once, using many sequencing reactions in parallel on a single instrument run. This massively parallel approach is what gave next-generation sequencing its name and its huge leap in throughput and cost efficiency, allowing whole genomes or large panels to be read quickly.

Sanger sequencing, by contrast, reads one DNA fragment at a time using chain-termination methods and capillary electrophoresis, so its throughput is much lower and not described as sequencing millions of fragments in parallel. RT-PCR is an amplification technique for RNA or cDNA, not a sequencing method. Southern blot is a detection method that identifies DNA fragments with probes, not sequences them.