Thread by @Biotech2k1

Looking at $PACB science:

Digging into how Single Molecule, Real Time (SMRT) technology.

1/ The SMRT technology takes advantage of DNA synthesis. To understand it, we must do a brief review of DNA synthesis. When DNA gets copied, a single strand of DNA gets copied by the DNA polymerase enzyme.

2/ The nucleotides are picked up by the DNA polymerase and incorporated into the new strand of DNA that is being built that is an exact opposite copy of the template strand.

3/ The $PACB Sequencer uses nucleotides that are each marked with a different dye color on their phosphate group. Each different base of A, G, T and C are marked with a different color dye.

4/ As the tagged nucleotide is incorporated into the new stand of DNA, that dye is cleaved off of the phosphate group. The Sequencer uses light wave lengths to read those lights emitted from when the dye is released from the phosphate.

5/ This allows for the real time sequencing of a single piece of DNA. Using this process, they can sequence up to 15,000 bases of DNA with over 99.9% accuracy. This system can read DNA, RNA and even epigenetic patterns of the DNA.

6/ This is what is classified as long read sequencing as the older short reads could only sequence up to 1,000 bases. The Sequel II can run 8 million DNA samples simultaneously at a time.

7/ There are a lot of consumables that go into this process which makes the consumable about half of the sales for $PACB. They generate sales of the machines, but they also generate reoccurring revenues from the consumables.

8/ This process differs from that used by Oxford Nanopore. They use a signal frequency that changes as each base of the DNA passes through the nanopore. The signal will have a different frequency change based on which nucleotide passes though the nanopore.

9/ There are advantages and disadvantages of each technology. $PACB tends to be more expensive and does shorter reads then Oxford Nanopore. The time and accuracy tends to be better for $PACB.