Next-generation Methods
The high demand for low-cost sequencing has driven the development of high-throughput sequencing (or next-generation sequencing) technologies that parallelize the sequencing process, producing thousands or millions of sequences at once. High-throughput sequencing technologies are intended to lower the cost of DNA sequencing beyond what is possible with standard dye-terminator methods. In ultra-high-throughput sequencing as many as 500,000 sequencing-by-synthesis operations may be run in parallel.
| Method | Single-molecule real-time sequencing (Pacific Bio) | Ion semiconductor (Ion Torrent sequencing) | Pyrosequencing (454) | Sequencing by synthesis (Illumina) | Sequencing by ligation (SOLiD sequencing) | Chain termination (Sanger sequencing) |
|---|---|---|---|---|---|---|
| Read length | 2900 bp average | 200 bp | 700 bp | 50 to 250 bp | 50+35 or 50+50 bp | 400 to 900 bp |
| Accuracy | 87% (read length mode), 99% (accuracy mode) | 98% | 99.9% | 98% | 99.9% | 99.9% |
| Reads per run | 35-75 thousand | up to 5 million | 1 million | up to 3 billion | 1.2 to 1.4 billion | N/A |
| Time per run | 30 minutes to 2 hours | 2 hours | 24 hours | 1 to 10 days, depending upon sequencer and specified read length | 1 to 2 weeks | 20 minutes to 3 hours |
| Cost per 1 million bases (in US$) | $2 | $1 | $10 | $0.05 to $0.15 | $0.13 | $2400 |
| Advantages | Longest read length. Fast. Detects 4mC, 5mC, 6mA. | Less expensive equipment. Fast. | Long read size. Fast. | Potential for high sequence yield, depending upon sequencer model and desired application. | Low cost per base. | Long individual reads. Useful for many applications. |
| Disadvantages | Low yield at high accuracy. Equipment can be very expensive. | Homopolymer errors. | Runs are expensive. Homopolymer errors. | Equipment can be very expensive. | Slower than other methods. | More expensive and impractical for larger sequencing projects. |
Read more about this topic: DNA Sequencing
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