Skip to content

Method for Mapping Bisulfite-treated Sequencing Reads To a Genome

License

Notifications You must be signed in to change notification settings

SKosier/MasterThesisFER

Repository files navigation

Master thesis - Method for Mapping Bisulfite-treated Sequencing Reads To a Genome

Overview

This is full code part of master thesis for Faculty of Electrical Engineering and Computing. Goal was to develop method for mapping bisulfite-treated sequencing reads to a genome using some of already existing mapping tools. The work is based on Accel-align tool: https://github.com/raja-appuswamy/accel-align-release

Get started

Pre-requirement

Since BisulfiteAligner uses Accel-align under-the-hood, there is TBB dependency

Intel TBB

Installation

Build index

It's mandatory to build the index before alignment. Options:

-l INT the length of k-mers [32]

Example:

path-to-bisulfite-aligner/bsfindex -l 32 path-to-ref/ref.fna

It will generate two indices aside the reference genome as path-to-ref/ref.fna.ct_hash and path-to-ref/ref.fna.ga_hash.

Align

When the alignment is triggered, the index will be loaded in memory automatically.

Options:

   -t INT number of cpu threads to use [1].
   -l INT length of seed [32].
   -o name of output file to use.
   -x alignment-free.
   -w use WFA for extension. It's using KSW by default.
   -p the maximum distance allowed between the paired-end reads [1000].
   -d disable embedding, extend all candidates from seeding (this mode is super slow, only for benchmark).
   Note: maximum read length and read name length supported are 512.

Pair-end alignment

path-to-bisulfite-aligner/bsfalign options ref.fna read1.fastq read2.fastq

Example:

path-to-bisulfite-align/bsfalign -l 32 -t 4 -o output-path/out.sam \
path-to-ref/ref.fna input-path/read1.fastq input-path/read2.fastq

Single-end alignment

path-to-bisulfite-aligner/bsfalign options ref.fna read.fastq

Example:

path-to-bisulfite-aligner/bsfalign -l 32 -t 4 -o output-path/out.sam \
path-to-ref/ref.fna input-path/read.fastq

Reference to Accel-align

Paper about Accel-align can be found here https://doi.org/10.1186/s12859-021-04162-z :

Yan, Y., Chaturvedi, N. & Appuswamy, R. Accel-Align: a fast sequence mapper and aligner based on the seed–embed–extend method. BMC Bioinformatics 22, 257 (2021).

About

Method for Mapping Bisulfite-treated Sequencing Reads To a Genome

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Languages