What are the key principles of next-generation sequencing and how does it differ from Sanger sequencing?

What are the key principles of next-generation sequencing and how does it differ from Sanger sequencing?

• A. NGS sequences millions of fragments in parallel by sequencing-by-synthesis or similar methods, producing large data sets; Sanger is a single-read chain-termination method.
• B. NGS uses capillary electrophoresis; Sanger uses sequencing-by-synthesis.
• C. Sanger sequences millions in parallel; NGS sequences single read.
• D. NGS and Sanger are identical in throughput and data output.

Answer: (A)

Massively parallel sequencing is the defining idea. Next-generation sequencing reads millions of DNA fragments at once, typically by attaching fragments to a surface or beads and using sequencing-by-synthesis (or another parallel detection method). Each cycle reveals which base was added across all fragments, so you end up with enormous amounts of short reads that must be stitched together or aligned computationally. Sanger sequencing, on the other hand, works with a single DNA fragment per reaction and uses chain termination with labeled dideoxynucleotides; the fragments are separated by size in capillary electrophoresis to read the sequence. Because only one read is produced at a time, Sanger has very high accuracy per read but far lower throughput and data output compared with NGS. This is why the description stating that NGS sequences millions of fragments in parallel to generate large datasets, while Sanger is a single-read chain-termination method, is the best answer.

Massively parallel sequencing is the defining idea. Next-generation sequencing reads millions of DNA fragments at once, typically by attaching fragments to a surface or beads and using sequencing-by-synthesis (or another parallel detection method). Each cycle reveals which base was added across all fragments, so you end up with enormous amounts of short reads that must be stitched together or aligned computationally. Sanger sequencing, on the other hand, works with a single DNA fragment per reaction and uses chain termination with labeled dideoxynucleotides; the fragments are separated by size in capillary electrophoresis to read the sequence. Because only one read is produced at a time, Sanger has very high accuracy per read but far lower throughput and data output compared with NGS. This is why the description stating that NGS sequences millions of fragments in parallel to generate large datasets, while Sanger is a single-read chain-termination method, is the best answer.