20-bismark.sh

#!/bin/bash
## Job Name - can be changed
#SBATCH --job-name=BISMARK
## Allocation Definition - confirm correctness
#SBATCH --account=coenv
#SBATCH --partition=coenv
## Resources
## Nodes (often you will only use 1)
#SBATCH --nodes=1
## Walltime (days-hours:minutes:seconds format)
#SBATCH --time=30-00:00:00
## Memory per node
#SBATCH --mem=120G
## email notification
#SBATCH --mail-type=ALL
#SBATCH --mail-user=$USER@uw.edu
## Specify the working directory for this job
#SBATCH --workdir=
# Exit script if a command fails
set -e

##########################
# This is a script written to assess bisulfite sequencing reads
# using Bismark. The user needs to supply the following:
# 1. A single directory location contaning BSseq reads.
# 2. BSseq reads need to be gzipped FastQ and end with .fq.gz
# 3. A bisulfite-converted genome, produced with Bowtie2.
# 4. Indicate if deduplication should be performed (whole genome or reduced genome sequencing)
#
# Set these values below



### USER NEEDS TO SET VARIABLES FOR THE FOLLOWING:
# Set --workdir= path in SBATCH header above.
#
# Full path to directory with sequencing reads
reads_dir=""

# Full path to bisulftie-converted genome directory
genome_dir=""

# Enter y (for yes) or n (for no) between the quotes.
# Yes - Whole genome bisulfite sequencing, MBD.
# No - Reduced genome bisulfite sequencing (e.g. RRBS)
deduplicate=""

# Run Bismark on desired number of reads/pairs subset
# The default value is 0, which will run Bismark on all reads/pairs
subset="-u 0"

####################################################
# DO NOT EDIT BELOW THIS LINE
####################################################




# Evaluate user-edited variables to make sure they have been filled
[ -z ${deduplicate} ] \
&& { echo "The deduplicate variable is not defined. Please edit the SBATCH script and add y or n to deduplicate variable."; exit 1; }

[ -z ${genome_dir} ] \
&& { echo "The bisulfite genome directory path has not been set. Please edit the SBATCH script."; exit 1; }

[ -z ${reads_dir} ] \
&& { echo "The reads directory path has not been set. Please edit the SBATCH script."; exit 1; }



# Directories and programs
wd=$(pwd)
bismark_dir="/gscratch/srlab/programs/Bismark-0.21.0_dev"
bowtie2_dir="/gscratch/srlab/programs/bowtie2-2.3.4.1-linux-x86_64/"
samtools="/gscratch/srlab/programs/samtools-1.9/samtools"
threads="28"
reads_list="input_fastqs.txt"

## Concatenated FastQ Files
R1=""
R2=""

# Initialize arrays
R1_array=()
R2_array=()

# Create list of input FastQ files for easier confirmation.
for fastq in ${reads_dir}/*.fq.gz
do
  echo ${fastq##*/} >> ${reads_list}
done

# Check for paired-end
# Capture grep output
# >0 means single-end reads
# set +e/set -e prevents error >0 from exiting script
set +e
grep "_R2_" ${reads_list}
paired=$?
set -e

# Confirm even number of FastQ files
num_files=$(wc -l < ${reads_list})
fastq_even_odd=$(echo $(( ${num_files} % 2 )) )


## Save FastQ files to arrays
R1_array=(${reads_dir}/*_R1_*.fq.gz)
## Send comma-delimited list of R1 FastQ to variable
R1=$(echo ${R1_array[@]} | tr " " ",")

# Evaluate if paired-end FastQs
# Run Bismark as paired-end/single-end based on evaluation
if [[ ${paired} -eq 0 ]]; then
  # Evaluate if FastQs have corresponding partner (i.e. R1 and R2 files)
  # Evaluated on even/odd number of files.
  if [[ ${fastq_even_odd} -ne 0 ]]; then
    { echo "Missing at least one FastQ pair from paired-end FastQ set."; \
      echo "Please verify input FastQs all have an R1 and corresponding R2 file.";
      exit 1; \
    }
  fi
  ## Save FastQ files to arrays
  R2_array=(${reads_dir}/*_R2_*.fq.gz)
  ## Send comma-delimited list of R2 FastQ to variable
  R2=$(echo ${R2_array[@]} | tr " " ",")
  # Run bismark using bisulftie-converted genome
  # Generates a set of BAM files as outputs
  # Records stderr to a file for easy viewing of Bismark summary info
  ${bismark_dir}/bismark \
  --path_to_bowtie2 ${bowtie2_dir} \
  --genome ${genome_dir} \
  --samtools_path=${samtools} \
  --non_directional \
  ${subset} \
  -p ${threads} \
  -1 ${R1} \
  -2 ${R2} \
  2> bismark_summary.txt
else
  # Run Bismark single-end
  ${bismark_dir}/bismark \
  --path_to_bowtie2 ${bowtie2_dir} \
  --genome ${genome_dir} \
  --samtools_path=${samtools} \
  --non_directional \
  ${subset} \
  -p ${threads} \
  ${R1} \
  2> bismark_summary.txt
fi



# Determine if deduplication is necessary
# Then, determine if paired-end or single-end
if [ ${deduplicate} == "y"  ]; then
  # Sort Bismark BAM files by read names instead of chromosomes
  find *.bam \
  | xargs basename -s .bam \
  | xargs -I bam_basename \
  ${samtools} sort \
  --threads ${threads} \
  -n bam_basename.bam \
  -o bam_basename.sorted.bam
  if [ ${paired} -eq 0 ]; then
    # Deduplication
    find *sorted.bam \
    | xargs basename -s .bam \
    | xargs -I bam_basename \
    ${bismark_dir}/deduplicate_bismark \
    --paired \
    --samtools_path=${samtools} \
    bam_basename.bam
  else
    find *sorted.bam \
    | xargs basename -s .bam \
    | xargs -I bam_basename \
    ${bismark_dir}/deduplicate_bismark \
    --single \
    --samtools_path=${samtools} \
    bam_basename.bam
  fi
  # Methylation extraction
  # Extracts methylation info from deduplicated BAM files produced by Bismark
  # Options to created a bedgraph file, a cytosine coverage report, counts, remove spaces from names
  # and to use the "scaffolds" setting.
  ${bismark_dir}/bismark_methylation_extractor \
  --bedGraph \
  --cytosine_report \
  --genome_folder ${genome_dir} \
  --gzip
  --counts \
  --scaffolds \
  --remove_spaces \
  --multicore ${threads} \
  --buffer_size 75% \
  --samtools_path=${samtools} \
  *deduplicated.bam
  # Sort deduplicated BAM files
  find *deduplicated.bam \
  | xargs basename -s .bam \
  | xargs -I bam_basename \
  ${samtools} sort \
  --threads ${threads} \
  bam_basename.bam \
  -o bam_basename.sorted.bam
  # Index sorted files for IGV
  # The "-@ ${threads}" below specifies number of CPU threads to use.
  find *deduplicated.sorted.bam \
  | xargs -I sorted_bam \
  ${samtools} index \
  -@ ${threads} \
  sorted_bam
else
  # Methylation extraction
  # Extracts methylation info from BAM files produced by Bismark
  # Options to created a bedgraph file, a cytosine coverage report, counts, remove spaces from names
  # and to use the "scaffolds" setting.
  ${bismark_dir}/bismark_methylation_extractor \
  --bedGraph \
  --cytosine_report \
  --genome_folder ${genome_dir} \
  --gzip \
  --counts \
  --scaffolds \
  --remove_spaces \
  --multicore ${threads} \
  --buffer_size 75% \
  --samtools_path=${samtools} \
  *.bam

  # Sort BAM files
  find *.bam \
  | xargs basename -s .bam \
  | xargs -I bam_basename \
  ${samtools} sort \
  --threads ${threads} \
  -o bam_basename.sorted.bam
  # Index sorted files for IGV
  # The "-@ ${threads}" below specifies number of CPU threads to use.
  find *sorted.bam \
  | xargs -I sorted_bam \
  ${samtools} index \
  -@ ${threads} \
  sorted_bam
fi


# Bismark processing report
# Generates HTML reports from previously created files
${bismark_dir}/bismark2report

#Bismark summary report
# Generates HTML summary reports from previously created files
${bismark_dir}/bismark2summary