ScanIndel on Biowulf

Quick Links

ScanIndel is a small python program that ties together a number of third party tools to detect indels. From the ScanIndel GitHub page:

ScanIndel is a python program to detect indels (insertions and deletions) from NGS data by re-align and de novo assemble soft clipped reads.

References:

R. Yang, A. C. Nelson, C. Henzler, B. Thyagarajan, and K. A. Silverstein. ScanIndel: a hybrid framework for indel detection via gapped alignment, split reads and de novo assembly. Genome Medicine 2015, 7:127. Pubmed | PMC | Journal

Documentation

Github

Important Notes

Module Name: scanindel (see the modules page for more information)
ScanIndel uses bwa mem to align reads and is hardwired to use 8 threads. Therefore batch and interactive jobs should be submitted with --cpus-per-task=8.
Example files in $SCANINDEL_TEST_DATA

Interactive job

Interactive jobs should be used for debugging, graphics, or applications that cannot be run as batch jobs.

Allocate an interactive session and run the program. Sample session:

[user@biowulf]$ sinteractive --gres=lscratch:10 --mem=30g --cpus-per-task=8
salloc.exe: Pending job allocation 46116226
salloc.exe: job 46116226 queued and waiting for resources
salloc.exe: job 46116226 has been allocated resources
salloc.exe: Granted job allocation 46116226
salloc.exe: Waiting for resource configuration
salloc.exe: Nodes cn3144 are ready for job

[user@cn3144]$ module load scanindel
[user@cn3144]$ cd /lscratch/$SLURM_JOB_ID
[user@cn3144]$ cp -r $SCANINDEL_TEST_DATA .
[user@cn3144]$ cd example
[user@cn3144]$ mkdir hg19
[user@cn3144]$ ln -s /fdb/genomebrowser/gbdb/hg19/hg19.2bit hg19
[user@cn3144]$ cat input_data/config.txt
#name=path
bwa=/fdb/igenomes/Homo_sapiens/UCSC/hg19/Sequence/BWAIndex/genome.fa
blat=hg19
freebayes=/fdb/igenomes/Homo_sapiens/UCSC/hg19/Sequence/BWAIndex/genome.fa
[user@cn3144]$ ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample.txt
...
[user@cn3144]$ ls -lh
...
-rw-r--r-- 1 user group 8.4K May 21 14:27 test.assembly.indel.vcf
-rw-r--r-- 1 user group  868 May 21 14:27 test.contigs.bam
-rw-r--r-- 1 user group  28K May 21 14:27 test.contigs.bam.bai
-rw-r--r-- 1 user group 8.4K May 21 14:27 test.mapping.indel.vcf
-rw-r--r-- 1 user group    0 May 21 14:27 test.merged.indel.vcf
-rw-r--r-- 1 user group 160K May 21 14:26 test.reads.bam
-rw-r--r-- 1 user group  29K May 21 14:26 test.reads.bam.bai

[user@cn3144]$ exit
salloc.exe: Relinquishing job allocation 46116226
[user@biowulf]$

Batch job

Most jobs should be run as batch jobs.

Create a batch input file (e.g. ScanIndel.sh) similar to the following example:

#! /bin/bash

module load scanindel/1.3 || exit 1
ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample.txt

Submit this job using the Slurm sbatch command.

sbatch --cpus-per-task=8 --mem=30g ScanIndel.sh

Swarm of Jobs

A swarm of jobs is an easy way to submit a set of independent commands requiring identical resources.

Create a swarmfile (e.g. ScanIndel.swarm). For example:

ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample1.txt
ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample2.txt
ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample3.txt
ScanIndel.py -F 0 -p input_data/config.txt -i input_data/sample4.txt

Submit this job using the swarm command.

swarm -f ScanIndel.swarm -g 30 -t 8 --module ScanIndel/1.3

where

-g #	Number of Gigabytes of memory required for each process (1 line in the swarm command file)
-t #	Number of threads/CPUs required for each process (1 line in the swarm command file).
--module ScanIndel	Loads the ScanIndel module for each subjob in the swarm