---
title: "Bounded GRCh38 reference and MANE translation window"
method: GET
path: "/sessions/{session_id}/browser/reference"
tags: ["browser"]
---

# Bounded GRCh38 reference and MANE translation window

`GET /sessions/{session_id}/browser/reference`

## Request

- Base URL: `https://api.helena.bio` (the document declares no server; this is the origin it was published from)
- URL: `https://api.helena.bio/sessions/{session_id}/browser/reference`
- Auth: HTTP bearer

Return the mounted GRCh38 bases and one overlapping MANE coding model.

This is an authenticated, org-scoped and strictly bounded read-only surface.
It is intentionally unavailable above base-level zoom so a pan cannot turn
into an unbounded reference transfer.

## Path parameters

- `session_id` string, uuid, required

## Query parameters

- `chrom` string, required: Chromosome (bare or chr-prefixed)
- `start` integer, required: 1-based inclusive window start
- `end` integer, required: 1-based inclusive window end

## Response `200`

Successful Response

- BrowserReferenceResponse
  - `chrom` string, required
  - `start` integer, required
  - `end` integer, required
  - `sequence` string, required
  - `transcript` BrowserReferenceTranscriptOut
    - `geneSymbol` string, required
    - `transcriptId` string, required
    - `proteinId` string, nullable
    - `strand` string, required
    - `exons` array[]
      - integer[]
    - `cds` array[]
      - integer[]
    - `codons` BrowserReferenceCodonOut[]
      - `bases` string, required
      - `aminoAcid` string, required
      - `proteinPosition` integer, required
      - `genomicPositions` integer[], required

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service.md) · [All operations](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service/llms.txt) · [OpenAPI document](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service/revisions/fe51fd20cdf1?raw)