1 Alignment Data

1.1 SAMs and BAMs

1.1.1 Downloading alignment data (BAM)

cd ../data
curl -O https://gannet.fish.washington.edu/seashell/bu-mox/scrubbed/120321-cvBS/19F_R1_val_1_bismark_bt2_pe.deduplicated.sorted.bam
curl -O https://gannet.fish.washington.edu/seashell/bu-mox/scrubbed/120321-cvBS/19F_R1_val_1_bismark_bt2_pe.deduplicated.sorted.bam.bai

cd ../data
curl -O https://gannet.fish.washington.edu/seashell/bu-mox/data/Cvirg-genome/GCF_002022765.2_C_virginica-3.0_genomic.fa
curl -O https://gannet.fish.washington.edu/seashell/bu-mox/data/Cvirg-genome/GCF_002022765.2_C_virginica-3.0_genomic.fa.fai

1.1.2 Visualize with tview in terminal using:

/home/shared/samtools-1.12/samtools tview
../data/19F_R1_val_1_bismark_bt2_pe.deduplicated.sorted.bam
../data/GCF_002022765.2_C_virginica-3.0_genomic.fa

1.1.3 Aligning WGS data and visualizing in IGV

cd ../data
curl -O https://owl.fish.washington.edu/nightingales/C_gigas/F143n08_R2_001.fastq.gz
curl -O https://owl.fish.washington.edu/nightingales/C_gigas/F143n08_R1_001.fastq.gz

cd ../data
curl -O https://gannet.fish.washington.edu/panopea/Cg-roslin/cgigas_uk_roslin_v1_genomic-mito.fa
curl -O https://gannet.fish.washington.edu/panopea/Cg-roslin/cgigas_uk_roslin_v1_genomic-mito.fa.fai
curl -O https://gannet.fish.washington.edu/panopea/Cg-roslin/GCF_902806645.1_cgigas_uk_roslin_v1_genomic-mito.gtf

1.1.4 Alignment

/home/shared/hisat2-2.2.1/hisat2-build \
-f ../data/cgigas_uk_roslin_v1_genomic-mito.fa \
../output/cgigas_uk_roslin_v1_genomic-mito.index

/home/shared/hisat2-2.2.1/hisat2 \
-x ../output/cgigas_uk_roslin_v1_genomic-mito.index \
-p 4 \
-1 ../data/F143n08_R1_001.fastq.gz \
-2 ../data/F143n08_R2_001.fastq.gz \
-S ../output/F143_cgigas.sam

#Look at the data

tail -1 ../output/F143_cgigas.sam

#OR COULD (MAYBE) USE THIS:
tail -1 /home/shared/8TB_HDD_01/sr320/github/steven-coursework/assignments/output/F143_cgigas.sam

# Convert SAM to BAM, using 4 additional threads
/home/shared/samtools-1.12/samtools view -@ 4 -bS \
../output/F143_cgigas.sam > ../output/F143_cgigas.bam

# Sort the BAM file, using 4 additional threads
/home/shared/samtools-1.12/samtools sort -@ 4 \
../output/F143_cgigas.bam -o ../output/F143_cgigas_sorted.bam

# Index the sorted BAM file (multi-threading is not applicable to this operation)
/home/shared/samtools-1.12/samtools index \
../output/F143_cgigas_sorted.bam

1.1.5 mpileup using bcftools

/home/shared/bcftools-1.14/bcftools mpileup --threads 4 --no-BAQ \
--fasta-ref ../data/cgigas_uk_roslin_v1_genomic-mito.fa \
../output/F143_cgigas_sorted.bam > ../output/F143_mpileup_output.txt

tail ../output/F143_mpileup_output.txt

cat ../output/F143_mpileup_output.txt \
| /home/shared/bcftools-1.14/bcftools call -mv -Oz \
> ../output/F143_mpile.vcf.gz

zgrep "^##" -v ../output/F143_mpile.vcf.gz | \
awk 'BEGIN{OFS="\t"} {split($8, a, ";"); print $1,$2,$4,$5,$6,a[1],$9,$10}' | head

The code below might not work. That is fine. The VCF in the above chunk can be used for visualization in IGV.

/home/shared/bcftools-1.14/bcftools call \
-v -c ../output/F143_mpile.vcf.gz \
> ../output/F143_mpile_calls.vcf

1.1.6 Visualizing the data

1.1.6.1 screenshot of tview

1.1.6.2 bam file (raw)

tail -20 ../output/F143_cgigas.bam

06_alignment

Courtney Skalley

May 05, 2023