Definition
Reading sequences of more than 10,000 base pairs in a single continuous string.
Use in clinical context
Massively parallel sequencing (also known as next-generation sequencing) is very effective at finding small variants in DNA, such as changes to a single letter of the genetic code, but there are other types of variants that long-read sequencing can identify more accurately. These include changes where large sections of DNA are inserted, deleted or moved around, and copy number variants (CNVs). This is because, in massively parallel sequencing, the DNA is sequenced in short stretches and the entire DNA sequence has to be pieced back together after sequencing. This can result in ambiguity about where in the sequence a particular fragment has come from, or how many copies there are. These problems can be avoided when reading longer sequences in a single continuous string.
Long-read sequencing has promising applications in not only genomics but also in transcriptomics and epigenomics, as it can potentially read complete RNAs and detect methylation.
Related terms
Base pairs | Copy number variants | Deletions | Deoxyribonucleic acid (DNA) | Massively parallel sequencing | Next-generation sequencing | Read | Sanger sequencing | Sequencing | Variant
