>DNA sequencing Videos.

>With IBM tossing it’s hat into the ring of “next-next-generation” sequencing, I’m starting to get lost as to which generation is which. For the moment, I’m sort of lumping things together, while I wait to see how the field plays out. In my mind, first generation is anything that requires chain termination, Second generation is chemical based pyrosequencing, and third generation is single molecule sequencing based on a nano-scale mechanical process. It’s a crude divide, but it seems to have some consistency.

At any rate, I decided I’d collect a few videos to illustrate each one. For Sanger, there are a LOT of videos, many of which are quite excellent, but I only wanted one. (Sorry if I didn’t pick yours.) For second and third generation DNA sequencing videos, the selection kind of flattens out, and two of them come from corporate sites, rather than youtube – which seems to be the general consensus repository of technology videos.

Personally, I find it interesting to see how each group is selling themselves. You’ll notice some videos press heavily on the technology, while others focus on the workflow.

As an aside, I also find it interesting to look for places where the illustrations don’t make sense… there’s a lovely place in the 454 video where two strands of DNA split from each other on the bead, leaving the two full strands and a complete primer sequence… mysterious! (Yes, I do enjoy looking for inconsistencies when I go to the movies.)

Ok, get out your popcorn.

First Generation:
Sanger Entry: Link

Second Generation:
Pyrosequencing Entry: Link

Helicose Entry: Link

Illumina (Corporate site): Link

(Click to see the Flash animation)

454 Entry: Link

Third Generation:

Pacific Biosciences: Link

(Click to see the Flash Video)

Oxford Nanopore Entry: Link

IBM’s Entry: Link

Note: If I’ve missed something, please let me know. I’m happy to add to this post whenever something new comes up.

>Pacific Biotech new sequencing technology

>I have some breaking news. I doubt I’m the first to blog this, but I find it absolutely amazing, so I had to share.

Steve Turner from Pacific Biosciences (PacBio), just gave the final talk of the AGBT session, and it was damn impressive. They have a completely new method of doing sequencing that uses DNA polymerase as a sequencing engine. Most impressively, they’ve completed their proof of concept, and they presented data from it in the session.

The method is called Single Molecule Real Time (SMRT) sequencing. It’s capable of producing 5000-25,000 base pair reads, at a rate of 10 bases/second. (They apparently have 25bps techniques in development, and expect to release when they have 50bps working!)

The machinery has zero moving part, and once everything is in place, they anticipate that they’ll have a sequencing rate of greater than 100 Gb per hour! As they are proud to mention, that’s about a full draft genome for a human being in 15 minutes, and at a cost of about $100. Holy crap!