> For the complete documentation index, see [llms.txt](https://doc.duaer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.duaer.com/getting-started/gtex-expression.md).

# Search GTEx expression in Duaer

In Duaer, look up GTEx median tissue expression for a gene. One successful search uses 1 credit.
## What you get

GTEx expression in the Duaer data market uses 1 credit per successful search.

Related: [gtex-eqtl](/getting-started/gtex-eqtl.md).

## Search on the canvas

1. Open the node creator, pick Duaer Data → GTEx expression .
2. Fill Words (default BRCA1) or ID.
3. Limit defaults to 10, max 20. Execute.

A successful search uses 1 credit.

## Call the API

- GET https://api.duaer.com/v1/data/gtex-expression?...
- Authorization: Bearer <Duaer key>

The call skill below matches Copy skill.

## Call skill

Same text as Copy skill.

```
---
name: duaer-gtex-expression
description: >-
  Look up GTEx median tissue expression for a gene through Duaer.
  One successful search uses 1 Duaer credit.
---

# Duaer GTEx expression

Look up GTEx median tissue expression for a gene through Duaer with a Duaer key.

## Call

`GET https://api.duaer.com/v1/data/gtex-expression?words=BRCA1&limit=10`

Provide `words` or `id`.
- `words` — gene symbol, such as BRCA1.
- `id` — optional. Gencode id such as ENSG00000012048.20.
- `limit` — optional. From 1 to 20. Default 10.

## Result

Each item has `source`, `title`, `url`, `summary`, `geneSymbol`, `gencodeId`, `tissue`, and `median`.

```
## Questions

### How many credits does a GTEx expression search use in Duaer?

One successful search uses 1 credit.