PyamilySeq

PyamilySeq builds gene-family and pangenome summaries from CD-HIT, MMseqs2, BLAST, or DIAMOND clustering results. It supports species- and genus-level prevalence groups, staged reclustering, sequence export and alignment, visual exploration, input validation, and genomic-location analysis.

PyamilySeq extends the gene-family workflow developed for StORF-Reporter. If you use it in published work, please cite the PyamilySeq publication.

Core Guarantees

PyamilySeq 1.5 uses one canonical family ledger for every downstream output.

Features

• End-to-End: PyamilySeq can take a directory of GFF+FASTA files, run CD-HIT for clustering and process the results.
• Clustering input: Supports input from CD-HIT formatted files as well as CSV and TSV node-edge lists (MMseqs2 and -outfmt 6 from BLAST/DIAMOND).
• Reclustering: Allows for the addition of new sequences post-initial clustering - Ensures continuity of contemporary clustering results and highlights impact of novel gene predictions.
• 'Genus Mode': Unlike other 'pangenome' tools, PyamilySeq can identify gene groups found across multiple genera as unique entities (see below).
• Output: Generates a 'Roary/Panaroo' formatted presence-absence CSV formatted file for downstream analysis.
  • User-define species-/genus-wide gene groups - User has control over grouping parameters (core = 99/95% or min 6 genera etc).
  • Aligns representative sequences using MAFFT.
  • Output concatenated aligned sequences for tree building.
  • Optionally output sequences of each separate identified gene group.
  • Group-Splitter tool to split multi-copy gene groups.
  • Numerous additional tools to assist in the pre- and post-processing of data.

These checks address a common failure mode in pangenome pipelines: genes being silently dropped because they do not appear in a cluster file.

Installation

PyamilySeq requires Python 3.10 or newer.

python -m pip install PyamilySeq

For optional analysis libraries used by auxiliary workflows:

python -m pip install 'PyamilySeq[analysis]'

Full mode requires CD-HIT (cd-hit-est for DNA or cd-hit for amino-acid input). Alignment output requires MAFFT. External command failures stop the run and report the failing command instead of producing partial output.

Quick Start

Partial mode consumes an existing clustering result and the authoritative FASTA:

PyamilySeq Partial \
  -clustering_format CD-HIT \
  -cluster_file clusters.clstr \
  -original_fasta genes.fasta.gz \
  -output_dir PyamilySeq_Output \
  -gene_group_table \
  -core_group_table \
  --visualize

Full mode extracts or combines input sequences, runs CD-HIT, and processes the result:

PyamilySeq Full \
  -input_type combined \
  -input_dir genomes \
  -name_split_gff _combined.gff3 \
  -output_dir PyamilySeq_Output \
  --visualize

Run PyamilySeq Full --help or PyamilySeq Partial --help for the complete option list. --log and --log-dir are accepted before or after the mode name.

One-command supplementation workflow

Supplementation runs the full analysis on the original genomes, then clusters the original representatives with the added genomes and writes the combined analysis. Each input set can independently be a directory of combined GFF files, a directory of paired GFF/FASTA files, or an extracted FASTA. Results are kept under original/ and supplemented/ in the output directory.

PyamilySeq Supplementation \
  -original_input_type combined \
  -original_input_dir original_genomes \
  -original_name_split_gff .gff \
  -supplement_input_type combined \
  -supplement_input_dir added_genomes \
  -supplement_name_split_gff .gff \
  -output_dir supplementation_results \
  -sequence_type AA \
  -c 0.90 -s 0.80 -T 16 -M 8000

For extracted FASTA inputs, use -original_input_type fasta -original_input_fasta original_genes.fasta and the corresponding -supplement_input_type fasta -supplement_input_fasta added_genes.fasta. Protein or nucleotide alphabets are detected automatically. New FASTA headers must identify their genome using the configured sequence delimiter (by default, genome|gene).

Identifier And Taxon Rules

By default, sequence IDs use genome|gene, and the text before the first | is treated as the genome. Change this with --sequence-delimiter.

For ambiguous identifiers or genus analyses, provide --taxon-map. The map may be tab- or comma-separated and may contain either:

identifier<TAB>taxon
identifier<TAB>genome<TAB>taxon

An identifier may be a complete sequence ID or a genome prefix. Exact sequence mappings take precedence. In Genus mode, the historical fallback is the text before the first underscore in the genome ID; an explicit map is recommended.

Add genomes to a reclustered pangenome

Run Partial mode with the original cluster file, a FASTA containing the original and added genes, and a second clustering result made from that same combined FASTA. --added-genomes writes gene-level family links, a per-genome summary, an SVG chart, and an HTML report. --added-genomes accepts comma-separated IDs or a text file with one genome ID per line. source_families and source_clusters identify the original families reached by each added gene; only_Second families have no original family link.

PyamilySeq Partial \\
  -clustering_format CD-HIT \\
  -cluster_file original.clstr \\
  -reclustered original_plus_new.clstr \\
  -original_fasta original_plus_new_genes.fasta \\
  -output_dir extension_output \\
  --added-genomes new_isolate_1,new_isolate_2

Query genomes in an existing pangenome

PyamilySeq-Query accepts a PyamilySeq/Roary presence-absence CSV and a text file containing one genome column name per line. It reports family and gene counts for core and accessory families (core defaults to presence in at least 99% of genomes), plus a family-level table with matching gene IDs.

PyamilySeq-Query --gpa PyamilySeq_Output/gene_presence_absence.csv \\
  --genomes requested_genomes.txt --output-dir genome_query --core-percent 99

Clustering Inputs

CD-HIT

Use the native .clstr file. Representatives and the final cluster are parsed without relying on cluster numbering.

MMseqs2

Use the standard two-column representative/member TSV. Repeated or non-contiguous representative rows are combined into one family.

BLAST Or DIAMOND

Two-column files are interpreted as explicit undirected family edges. Scored tabular files use reciprocal-best edges by default to reduce weak-hit chaining. For standard outfmt 6 input:

PyamilySeq Partial \
  -clustering_format BLAST \
  -cluster_file hits.tsv \
  -original_fasta genes.fasta \
  -output_dir output \
  --blast-min-identity 90 \
  --blast-max-evalue 1e-10

Use --blast-columns when the input column order differs. Query and subject coverage filters require qlen and slen in that schema. The legacy connected component interpretation remains available as --blast-graph-mode connected-components, but can overmerge families through weak bridge hits.

Reclustering

Pass a second clustering result with -reclustered:

PyamilySeq Partial \
  -clustering_format CD-HIT \
  -cluster_file original.clstr \
  -reclustered original_and_novel.clstr \
  -original_fasta original_and_novel.fasta \
  -output_dir reclustered_output

Final families receive mutually exclusive provenance stages:

• First: an unchanged source family containing no second-round-only genes.
• extended: one source family plus new genes.
• combined: multiple source families merged by reclustering, with or without new genes.
• only_Second: genes that were absent from the first clustering, including singleton backfills.

The source_families and source_clusters columns preserve the reconciliation history.

Main Outputs

Every run writes:

• gene_family_assignments.tsv: the authoritative one-row-per-input-gene ledger, including genome, taxon, representative, stage, category, and source provenance.
• family_summary.tsv: one row per selected final family with prevalence, copy-number, representative, and provenance statistics.
• gene_presence_absence.csv: Roary/Panaroo-compatible family-by-genome table, unless -no_gpa is used.
• pan_genome_reference.fa: one deterministic representative per selected final family.
• summary_statistics.txt: category and assignment totals.
• run_manifest.json: inputs, parameters, stage counts, and the exactly_once_assignment audit result.

-gene_group_table and -core_group_table add compact TSV mappings. -write_groups, -write_individual_groups, and -align produce sequence and alignment outputs from the same final-family selection. Core alignment requires exactly one sequence from every genome in each aligned family.

Species prevalence groups are configured with -species_groups (default 99,95,15). Genus groups use inclusive ranges such as 1-10. Categories are mutually exclusive and include every selected family, including the zero-percent accessory bin.

Single-Copy Filtering

--single_copy_only restricts analytical outputs to families with no multi-copy occupied genome. --single_copy_tolerance PERCENT permits that percentage of occupied genomes to be multi-copy. The complete gene_family_assignments.tsv is always retained so filtering never erases the input-to-family audit trail.

Visual Outputs

Add --visualize to write Visualisations/ with:

• category and prevalence SVG charts;
• presence/absence and copy-number heatmaps;
• family-size distribution;
• deterministic pangenome and strict-core accumulation curves with confidence ranges in pangenome_accumulation.tsv;
• matching TSV data tables;
• a searchable, filterable canvas-based pangenome explorer; and
• an HTML index linking all views.

Use --visualize-heatmap-limit, --visualize-permutations, and --visualize-seed to control scale and reproducibility. Static plots show a bounded number of rows, while TSV tables and the interactive explorer retain all selected families.

Input Validation

Validate clustering, FASTA, and optional GFF inputs independently:

PyamilySeq-Validate \
  --clusters clusters.clstr \
  --cluster-format CD-HIT \
  --fasta genes.fasta.gz \
  --gff-dir genomes \
  --outdir validation

The validator reports duplicate family membership, cluster IDs absent from the FASTA, FASTA genes requiring singleton backfill, ambiguous GFF aliases, mapping confidence, and mapping rate. Use --fail-on error, warning, or never for automation. Reports are machine-readable TSV/JSON plus a text summary.

Family Location Tracking

Track-Family-Locations maps final family members to GFF/GFF3 features and describes their genomic context:

Track-Family-Locations \
  --clusters PyamilySeq_Output/gene_presence_absence.csv \
  --cluster-format gpa \
  --gff-dir genomes \
  --outdir family_locations \
  --minimum-mapping-rate 0.95

The tracker supports plain or gzip-compressed GFF/GFF3 files. Its default --feature-layer auto prefers CDS loci and collapses parent/child and multipart features to prevent duplicate biological loci. Alternative layers are CDS, gene, and all.

Mapping is exact first, alias-aware second, and uniquely canonicalized last. Each result records its method and confidence. Use --min-mapping-confidence, --strict-mapping, and --minimum-mapping-rate to enforce quality thresholds. --id-map resolves known identifier differences explicitly.

Neighborhoods are transcription-relative by default, so upstream and downstream remain biologically meaningful on the minus strand. Outputs record:

• signed family architectures and strand patterns;
• neighbor multiplicity and conserved-order metrics;
• intergenic base-pair gaps;
• contig length, topology, topology provenance, and relative-position basis;
• boundary censoring and circular wrapping; and
• per-member mapping diagnostics.

Use --genomic-neighbors for genomic left/right order. Circular contigs may be declared with --circular-contigs, and combined GFF provenance can be supplied with --contig-genome-map. --unmapped-family-report-limit and --unmapped-token-report-limit bound terminal diagnostics while the complete member-level report remains on disk.

Outputs include family_locations.csv, family_summary.csv, member_mapping.tsv, unmapped_members.tsv, location_tracking_report.txt, neighbor_family_summary.tsv, neighborhood_architectures.tsv, GraphML, and HTML/SVG neighborhood views. Singleton families are included by default; use --skip-singletons to omit them.

Auxiliary Commands

• Seq-Combiner: extract and combine GFF/FASTA sequences.
• Group-Splitter: split multi-copy groups using sequence clustering.
• Group-Extractor: select groups from a presence/absence table.
• Group-Summary: summarize prevalence categories, including 0% and 100%.
• Group-Compare: compare family partitions independent of cluster row order.
• Group-Sizes: summarize family sizes.
• Seq-Finder: find matching group rows for sequence IDs.
• Seq-Extractor: extract requested full sequence identifiers.
• Track-Genome-Order: summarize genome contig architecture and strand-aware gene order from GFF/GFF3 files.
• PyamilySeq-Cohort: prepare reproducible genome cohorts, calculate Sourmash similarity groups, run a global PyamilySeq pangenome, and stratify breakpoints by similarity group.

Each command provides its full interface with --help.

Track-Genome-Order --gff-dir genomes --outdir genome_order --no-plots writes tabular contig and gene-order reports. Add --family-map to compare shared families and infer contig orientation against a reference genome. Install PyamilySeq[analysis] to enable the figures. Orientation inference uses single-copy family anchors and requires both --min-orientation-anchors and --min-orientation-tau; ambiguous reference-contig matches remain unoriented. The tool expects unique GFF feature IDs for multipart features and reports partial family-map coverage and annotation/FASTA mismatches in run_summary.txt.

Cohort workflow for 100–1,000 genomes

The cohort workflow validates one matching GFF and FASTA per genome, writes a manifest and managed input links, runs one global PyamilySeq pangenome, and uses Sourmash similarity groups only to stratify downstream summaries. It does not build separate pangenomes for each similarity group.

Sourmash is an external command-line requirement for cohort similarity analysis. Bioconda installations should provide it as a package dependency; PyPI installations must install the sourmash command separately with python -m pip install sourmash before running the similarity stage.

PyamilySeq-Cohort prepare \
  --fasta-dir assemblies/fasta --gff-dir assemblies/gff \
  --metadata cohort_metadata.tsv --outdir ecoli_cohort

PyamilySeq-Cohort similarity \
  --manifest ecoli_cohort/genome_manifest.tsv --outdir ecoli_cohort \
  --min-similarity 0.55

PyamilySeq-Cohort pangenome \
  --manifest ecoli_cohort/genome_manifest.tsv --outdir ecoli_cohort \
  --threads 16 --memory-mb 16000

PyamilySeq-Cohort order \
  --manifest ecoli_cohort/genome_manifest.tsv --outdir ecoli_cohort \
  --reference-genome MG1655 --no-plots

The Sourmash threshold is intentionally explicit and should be selected after reviewing the similarity matrix. Similarity groups use connected components, so chained links can place genomically distant samples in the same group; the edge table is retained to inspect those links. The main pangenome remains global. Order outputs include per-assembly endpoint evidence and a breakpoint_support_by_similarity_group.tsv summary with group denominators.

Development

python -m pip install -e '.[dev]'
pytest
python -m compileall -q src scripts

Continuous integration tests Python 3.10 and 3.12. Bug reports and reproducible examples are welcome at the issue tracker.