A genome visualization python package for comparative genomics
pyGenomeViz
Table of contents
- Overview
- Installation
- API Examples
- CLI Examples
- GUI (Web Application)
- HTML Viewer
- Inspiration
- Circular Genome Visualization
- Star History
Overview
pyGenomeViz is a genome visualization python package for comparative genomics implemented based on matplotlib. This package is developed for the purpose of easily and beautifully plotting genomic features and sequence similarity comparison links between multiple genomes. It supports genome visualization of Genbank/GFF format file and can be saved figure in various formats (JPG/PNG/SVG/PDF/HTML). User can use pyGenomeViz for interactive genome visualization figure plotting on jupyter notebook, or automatic genome visualization figure plotting in genome analysis scripts/workflow.
For more information, please see full documentation here.
Fig.1 pyGenomeViz example plot gallery
Fig.2 pyGenomeViz web application example (Demo Page)
Installation
Python 3.10 or later is required for installation.
Install PyPI package:
pip install pygenomeviz
Install conda-forge package:
conda install -c conda-forge pygenomeviz
Use Docker (Image Registry):
docker run -it --rm -p 8501:8501 ghcr.io/moshi4/pygenomeviz:latest pgv-gui -h
API Examples
Jupyter notebooks containing code examples below is available here.
Features
from pygenomeviz import GenomeViz
gv = GenomeViz() gv.setscalexticks(ymargin=0.5)
track = gv.addfeaturetrack("track", 1000) track.add_sublabel()
Add features to track
track.add_feature(50, 200, 1)
track.add_feature(250, 460, -1, fc="blue")
track.add_feature(500, 710, 1, fc="lime", lw=1.0)
track.add_feature(750, 960, 1, fc="magenta", lw=1.0, ec="grey", hatch="//")
gv.savefig("features.png")

Styled Features
from pygenomeviz import GenomeViz
gv = GenomeViz() gv.setscalebar(ymargin=0.5)
track = gv.addfeaturetrack("track", (1000, 2000)) track.add_sublabel()
Add styled features
track.add_feature(1000, 1100, 1, label="arrow")
track.add_feature(1120, 1220, -1, plotstyle="bigarrow", label="bigarrow", fc="red", lw=1)
track.add_feature(1240, 1340, 1, plotstyle="box", label="box", fc="blue")
track.add_feature(1360, 1480, 1, plotstyle="bigbox", label="bigbox", fc="limegreen")
track.add_feature(1500, 1620, -1, plotstyle="rbox", label="rbox", fc="magenta", ec="blue", lw=1)
track.add_feature(1640, 1740, -1, plotstyle="bigrbox", label="bigrbox", fc="grey")
track.addfeature(1760, 1860, 1, fc="lime", hatch="o", arrowshaft_ratio=0.2, label="arrow shaft = 0.2")
track.addfeature(1880, 1980, 1, fc="lime", hatch="/", arrowshaft_ratio=1.0, label="arrow shaft = 1.0")
gv.savefig("styled_features.png")

Tracks & Links
from pygenomeviz import GenomeViz
genome_list = [ ("genome 01", 1000, [(150, 300, 1), (500, 700, -1), (750, 950, 1)]), ("genome 02", 1300, [(50, 200, 1), (350, 450, 1), (700, 900, -1), (950, 1150, -1)]), ("genome 03", 1200, [(150, 300, 1), (350, 450, -1), (500, 700, -1), (700, 900, -1)]), ]
gv = GenomeViz(figtrackheight=0.7, trackaligntype="center") gv.setscalebar()
Set tracks & features
for genome in genome_list:
name, size, features = genome[0], genome[1], genome[2]
track = gv.addfeaturetrack(name, size)
track.add_sublabel()
for idx, feature in enumerate(features, 1):
start, end, strand = feature
track.addfeature(start, end, strand, plotstyle="bigarrow", lw=1, label=f"gene{idx:02d}", textkws=dict(rotation=0, vpos="top", hpos="center"))
Add links between "genome 01" and "genome 02"
gv.add_link(("genome 01", 150, 300), ("genome 02", 50, 200))
gv.add_link(("genome 01", 700, 500), ("genome 02", 900, 700))
gv.add_link(("genome 01", 750, 950), ("genome 02", 1150, 950))
Add links between "genome 02" and "genome 03"
gv.addlink(("genome 02", 50, 200), ("genome 03", 150, 300), color="skyblue", invertedcolor="lime", curve=True)
gv.addlink(("genome 02", 350, 450), ("genome 03", 450, 350), color="skyblue", invertedcolor="lime", curve=True)
gv.addlink(("genome 02", 900, 700), ("genome 03", 700, 500), color="skyblue", invertedcolor="lime", curve=True)
gv.addlink(("genome 03", 900, 700), ("genome 02", 1150, 950), color="skyblue", invertedcolor="lime", curve=True)
gv.savefig("tracksandlinks.png")

Exon Features
from pygenomeviz import GenomeViz
exon_regions1 = [(0, 210), (300, 480), (590, 800), (850, 1000), (1030, 1300)] exon_regions2 = [(1500, 1710), (2000, 2480), (2590, 2800)] exon_regions3 = [(3000, 3300), (3400, 3690), (3800, 4100), (4200, 4620)]
gv = GenomeViz() track = gv.addfeaturetrack("track", 5000)
Add exon features
track.addexonfeature(exonregions1, strand=1, plotstyle="box", label="box", textkws=dict(rotation=0, hpos="center"))
track.addexonfeature(exonregions2, strand=-1, plotstyle="arrow", label="arrow", textkws=dict(rotation=0, vpos="bottom", hpos="center"), patchkws=dict(fc="darkgrey"), intronpatch_kws=dict(ec="red"))
track.addexonfeature(exonregions3, strand=1, plotstyle="bigarrow", label="bigarrow", textkws=dict(rotation=0, hpos="center"), patch_kws=dict(fc="lime", lw=1))
gv.savefig("exon_features.png")

Genbank Features
from pygenomeviz import GenomeViz
from pygenomeviz.parser import Genbank
from pygenomeviz.utils import loadexamplegenbank_dataset
Parse Genbank file
gbkfiles = loadexamplegenbankdataset("yersinia_phage")
gbk = Genbank(gbk_files[0])
gv = GenomeViz(figtrackheight=0.7) gv.setscalebar(ymargin=0.5)
track = gv.addfeaturetrack(gbk.name, gbk.get_seqid2size())
for seg in track.segments: # Plot CDS features features = gbk.get_seqid2features()[seg.name] seg.add_features(features, lw=0.5) seg.add_sublabel()
gv.savefig("genbank_features.png")

GFF Features
from pygenomeviz import GenomeViz
from pygenomeviz.parser import Gff
from pygenomeviz.utils import loadexamplegff_file
gfffile = loadexamplegfffile("escherichia_coli.gff.gz") gff = Gff(gff_file)
gv = GenomeViz() gv.setscalebar(ymargin=0.5)
target_ranges = ((215000, 230000), (300000, 320000)) track = gv.addfeaturetrack(name=gff.name, segments=target_ranges) track.setsegmentsep()
for segment in track.segments: segment.add_sublabel() features = gff.extractfeatures(featuretype=None, target_range=segment.range) for feature in features: if feature.type == "CDS": segment.addfeatures(feature, labeltype="gene", fc="skyblue", lw=1.0, annotation=True, text_kws=dict(bbox=dict(boxstyle="round", fc="skyblue"))) elif feature.type == "rRNA": segment.addfeatures(feature, labeltype="product", fc="lime", lw=1.0, hatch="//", annotation=True, text_kws=dict(bbox=dict(boxstyle="round", fc="lime")))
gv.savefig("gff_features.png")

GFF Contigs
from pygenomeviz import GenomeViz
from pygenomeviz.parser import Gff
from pygenomeviz.utils import loadexamplegfffile, ispseudo_feature
gfffile = loadexamplegfffile("mycoplasma_mycoides.gff") gff = Gff(gff_file)
gv = GenomeViz(figtrackheight=0.5, featuretrackratio=0.5) gv.setscalexticks(labelsize=10)
Plot CDS, rRNA features for each contig to tracks
for seqid, size in gff.get_seqid2size().items():
track = gv.addfeaturetrack(seqid, size, labelsize=15)
track.add_sublabel(size=10, color="grey")
cdsfeatures = gff.getseqid2features(feature_type="CDS")[seqid]
# CDS: blue, CDS(pseudo): grey
for cdsfeature in cdsfeatures:
color = "grey" if ispseudofeature(cds_feature) else "blue"
track.addfeatures(cdsfeature, color=color)
# rRNA: lime
rrnafeatures = gff.getseqid2features(feature_type="rRNA")[seqid]
track.addfeatures(rrnafeatures, color="lime")
gv.savefig("gff_contigs.png")

Genbank Comparison by BLAST
from pygenomeviz import GenomeViz
from pygenomeviz.parser import Genbank
from pygenomeviz.utils import loadexamplegenbank_dataset
from pygenomeviz.align import Blast, AlignCoord
gbkfiles = loadexamplegenbankdataset("yersinia_phage") gbklist = list(map(Genbank, gbkfiles))
gv = GenomeViz(trackaligntype="center") gv.setscalebar()
Plot CDS features
for gbk in gbk_list:
track = gv.addfeaturetrack(gbk.name, gbk.getseqid2size(), alignlabel=False)
for seqid, features in gbk.get_seqid2features("CDS").items():
segment = track.get_segment(seqid)
segment.add_features(features, plotstyle="bigarrow", fc="limegreen", lw=0.5)
Run BLAST alignment & filter by user-defined threshold
aligncoords = Blast(gbklist, seqtype="protein").run()
aligncoords = AlignCoord.filter(aligncoords, lengththr=100, identitythr=30)
Plot BLAST alignment links
if len(align_coords) > 0:
minident = int(min([ac.identity for ac in aligncoords if ac.identity]))
color, inverted_color = "grey", "red"
for ac in align_coords:
gv.addlink(ac.querylink, ac.reflink, color=color, invertedcolor=invertedcolor, v=ac.identity, vmin=minident)
gv.setcolorbar([color, invertedcolor], vmin=min_ident)
gv.savefig("genbankcomparisonby_blast.png")

CLI Examples
pyGenomeViz provides CLI workflows for genome alignment result visualization of Genbank genomes using BLAST / MUMmer / MMseqs / progressiveMauve, respectively.
BLAST CLI Workflow
See pgv-blast document for details.
# Download example dataset
pgv-download yersinia_phage
Run BLAST CLI workflow
pgv-blast NC070914.gbk NC070915.gbk NC070916.gbk NC070918.gbk \
-o pgv-blastexample --seqtype protein --showscale_bar --curve \
--featurelinewidth 0.3 --lengththr 100 --identity_thr 30

MUMmer CLI Workflow
See pgv-mummer document for details.
# Download example dataset
pgv-download mycoplasma_mycoides
Run MUMmer CLI workflow
pgv-mummer GCF000023685.1.gbff GCF000800785.1.gbff GCF000959055.1.gbff GCF000959065.1.gbff \
-o pgv-mummerexample --showscale_bar --curve \
--feature_type2color CDS:blue rRNA:lime tRNA:magenta

MMseqs CLI Workflow
See pgv-mmseqs document for details.
# Download example dataset
pgv-download enterobacteria_phage
Run MMseqs CLI workflow
pgv-mmseqs NC013600.gbk NC016566.gbk NC019724.gbk NC024783.gbk NC028901.gbk NC031081.gbk \
-o pgv-mmseqsexample --showscalebar --curve --featurelinewidth 0.3 \
--featuretype2color CDS:skyblue --normallinkcolor chocolate --invertedlink_color limegreen

progressiveMauve CLI Workflow
See pgv-pmauve document for details.
# Download example dataset
pgv-download escherichia_coli
Run progressiveMauve CLI workflow
pgv-pmauve NC000913.gbk.gz NC002695.gbk.gz NC011751.gbk.gz NC011750.gbk.gz \
-o pgv-pmauveexample --showscale_bar

GUI (Web Application)
pyGenomeViz implements GUI (Web Application) functionality using streamlit as an option. Users can easily visualize the genomic features in Genbank files and their comparison results with GUI (Demo Page). See pgv-gui document for details.

HTML Viewer
pyGenomeViz implements HTML viewer output functionality for interactive data visualization. In API, HTML file can be output using savefig_html method. In CLI, user can select HTML file output option. As shown below, pan/zoom, tooltip display, object color change, text change, etc are available in HTML viewer (Demo Page1, Demo Page2).

Following libraries were used to implement HTML viewer.
- Spectrum: Colorpicker
- Panzoom: SVG panning and zooming
- Tabulator: Interactive Table
- Micromodal: Modal dialog
- Tippy.js: Tooltip
Inspiration
pyGenomeViz was inspired by
Circular Genome Visualization
pyGenomeViz is a python package designed for linear genome visualization. If you are interested in circular genome visualization, check out my other python package pyCirclize.
Fig. pyCirclize example plot gallery