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lecture_notes:04-29-2015

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Discovar denovo is by the  Broad institute. It is a total pipeline, meaning that one needs to follow the sequencing as well as assembly protocols to obtain the best results. Most of the information is the in the PPT here. The notes below are supplemental.

Basic Outline:
Builds stacks
Filters out crap
Builds consensus
Trys to merge stacks
Using pairwise windows. If it finds a match it checks adjacent windows for overlap before they link them
Correct paired ends against each other
Then build using HQ pairs

Before Assembly:
Spri beads size selection.
No amplification in adapter phase.
Wants a single library on an illumia machine.

Different Error Correction/Gap filling steps:
Use sequential error correction increasing in difficulty to reduce computation
Look for isolated loser calls which means no LQ scores adjacent and corrects the scores up.
Reduce quality scores in a sliding window.  Correct artifically high quality scores with adjacent low scores

Assembly:
Use the good founder pairs from previous steps to "seed" building the genome.
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lecture_notes/04-29-2015.1430335155.txt.gz · Last modified: 2015/04/29 12:19 by chkan