tbrowse

Embeddable React component for visualizing phylogenetic trees with pluggable data zones.

<TBrowse> renders a tree alongside a row-aligned set of zones (Tree, Labels, MSA, custom plug-ins). Tree topology, taxonomy, MSA, gene metadata, and per-node annotations are independent host inputs — TBrowse does no fetching of its own. View state (selection, collapse, prune, swap, zone widths, MSA viewport, search) is a single serializable object that round-trips through URL state via the controlled viewState / onViewStateChange props.

Status

2.0.0 is a complete rewrite of the original component on a fresh React 18 / TypeScript / Zustand stack. The 1.x line on npm (tbrowse@1.0.x) is the previous nwb / React 16 / Redux-Toolkit implementation, preserved at commit b017a74 for archival reference. The 2.0 API is not backwards-compatible with 1.x.

The rewrite is functionally complete: chassis, four built-in zones (Tree / Labels / MSA / Neighborhood), Ensembl REST and Gramene adapters, animated transitions, branch-length compression, gene-family coloring, protein-domain annotations, splice-junction marks, and a nodeOfInterest pivot. See CHANGELOG.md for the migration summary.

Quick start

import { TBrowse, treeZone, labelsZone, msaZone, type Tree, type MSA, type Taxonomy } from 'tbrowse';

const tree: Tree = { rootId: 'n0', nodes: { /* ... */ } };
const taxonomy: Taxonomy = { /* taxId → { scientificName, commonName, ... } */ };
const msa: MSA = { alphabet: 'protein', length: 60, sequences: { /* geneId → string */ } };

<div style={{ width: 900, height: 600 }}>
  <TBrowse
    tree={tree}
    taxonomy={taxonomy}
    msa={msa}
    zones={[treeZone, labelsZone, msaZone]}
  />
</div>

Live Ensembl example

The bundled Vite playground (npm run dev) has a "Load Ensembl tree" button that fetches a real gene tree (BRCA2 — ENSG00000139618) from rest.ensembl.org, runs it through fromEnsemblGeneTree, and renders it pivoted to put human BRCA2 at the top. Demonstrates the entire stack against live data.

import { fromEnsemblGeneTree, computePivotState, TBrowse } from 'tbrowse';

const json = await fetch(
  'https://rest.ensembl.org/genetree/member/id/homo_sapiens/ENSG00000139618?aligned=1&sequence=protein',
  { headers: { Accept: 'application/json' } },
).then((r) => r.json());

const { tree, taxonomy, msa, geneMetadata } = fromEnsemblGeneTree(json);

Development

npm install
npm run dev         # Vite dev server (examples/playground)
npm run typecheck   # tsc --noEmit
npm test            # vitest
npm run build       # library build to dist/

Host inputs

interface TBrowseProps {
  tree: Tree;                          // required
  taxonomy?: Taxonomy;
  msa?: MSA;
  geneMetadata?: GeneMetadata;
  nodeAnnotations?: NodeAnnotation[];
  labelProviders?: LabelProvider[];

  zones: ZoneDefinition[];             // built-ins + plugins
  nodeOfInterest?: string;             // pivot the tree to this gene/node at mount

  // Controlled / uncontrolled view state
  viewState?: ViewState;
  initialViewState?: Partial<ViewState>;
  onViewStateChange?: (next: ViewState) => void;

  theme?: 'light' | 'dark';
  className?: string;
}

Tree.nodes is flat: { id, parentId, distance, isLeaf, taxonomyId?, geneId?, eventType?, bootstrap? }. MSA.sequences is keyed by gene id. The Ensembl adapter (fromEnsemblGeneTree) walks the nested REST response into this normalized shape.

ViewState

The single serializable object that captures everything URL-shareable.

interface ViewState {
  selectedNodeId: NodeId | null;
  collapsedNodeIds: NodeId[];          // internal nodes shown as triangles
  prunedNodeIds: NodeId[];             // subtrees hidden + replaced with stub glyphs
  swappedNodeIds: NodeId[];            // internal nodes whose children render in reversed order
  zones: { id: string; width: number; visible: boolean }[];
  zoneStates: Record<string, unknown>; // per-zone state slot (built-ins use well-known keys)
  search: { field: string; query: string } | null;
}

All chassis interactions (resize, reorder, collapse via tooltip, prune via tooltip, swap, MSA pan/zoom, label-field picker, show/hide) write to this object via onViewStateChange. Persist it to a URL fragment for shareable views.

Built-in zones

Zone	Id	Default width
treeZone	tree	280px
labelsZone	labels	220px
msaZone	msa	360px

The Tree zone supports collapse/expand, prune/regrow, swap children, click-tooltip with contextual actions, internal-node event glyphs (speciation circle / duplication square), proportional-height collapsed-subtree triangles, and animated transitions. Labels supports a configurable field picker (gene id, gene name, gene description, scientific name, common name) plus optional async LabelProvider plug-ins. MSA renders a canvas alignment with a coverage minimap (drag-to-pan), wheel-driven pan + ctrl/shift-zoom, and four built-in color schemes (Plain, Clustal, Hydrophobicity, Nucleotide).

Custom zones implement ZoneDefinition:

interface ZoneDefinition<S = unknown> {
  id: string;
  displayName: string;
  Header: ComponentType<ZoneRenderProps<S>>;
  Body: ComponentType<ZoneRenderProps<S>>;
  defaultWidth: number;
  minWidth: number;
  defaultZoneState: S;
  isAvailable: (data: HostData) => boolean;
}

Both Header and Body receive the same ZoneRenderProps: visibleRows (already collapsed/pruned/swapped), virtualization rowRange, hover/select callbacks, the host's data, and per-zone state plumbing.

Helpers

Export	What
computeVisibleRows	Pure derivation: (tree, collapsed, pruned, swapped) → VisibleRow[].
computeTreeLayout	Pure phylogram layout against a column width.
computePivotState	Resolve a gene id / node id and return collapse + swap sets that pivot the tree.
fromEnsemblGeneTree	Convert Ensembl REST gene-tree JSON to TBrowse inputs.
createStubZone	Build a placeholder zone for development.

Bundle

ESM + CJS, types via vite-plugin-dts. Peer-deps on react / react-dom only; runtime dep on zustand. Current bundle ~14 kB gzipped (CJS).

Project layout

src/
  TBrowse.tsx, types.ts, store.tsx, treeIndex.ts
  visibleRows.ts        chassis row derivation
  pivot.ts              nodeOfInterest helper
  layout/               grid + virtualization + animation
  zones/
    tree/               SVG branches, glyphs, triangles, tooltip
    labels/             field picker, label-provider cache
    msa/                canvas paint, minimap, color schemes
  adapters/
    ensembl.ts          Ensembl REST → TBrowse inputs
  *.test.ts             vitest unit tests
examples/playground/    Vite dev app (kitchen-sink demo)

License

MIT.