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# List ModifiedNucleotide items

GET https://{tenant_name}.benchling.com/api/v3/dna-oligo/{dna_oligo_id}/modified-nucleotides/items

List ModifiedNucleotide items.

Reference: https://docs.benchling.com/docs/api/benchling-api/dna-oligo/modifiednucleotides-list

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Path parameters

- `dna_oligo_id` (string, required) — ID of the DnaOligo.

### Query parameters

- `nextToken` (string, optional) — Token for pagination
- `pageSize` (integer, optional) — Number of results to return. Defaults to 50, maximum of 100.

## Response

### 200

OK

- `items` (list of ModifiedNucleotide, optional)
- `nextToken` (string, optional)

## Errors

### 400 Dna Oligo Modified Nucleotides List Request Bad Request Error

Bad Request

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 403 Dna Oligo Modified Nucleotides List Request Forbidden Error

Forbidden

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 404 Dna Oligo Modified Nucleotides List Request Not Found Error

Not Found

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 429 Dna Oligo Modified Nucleotides List Request Too Many Requests Error

Too Many Requests

- `detail` (TooManyRequestsErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)
- `violated-policies` (list of enum, optional) — The budget policies that rejected the request, in canonical order: `user`, `integration`, then `tenant`.
  - Allowed values: `user`, `integration`, `tenant`

### 500 Dna Oligo Modified Nucleotides List Request Internal Server Error

Internal Server Error

- `detail` (InternalServerErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `errorId` (string, optional)

## Types

### ModifiedNucleotide

Represents a chemically modified nucleotide at a specific position in an oligonucleotide sequence. Each modification specifies the sugar, base, and phosphate monomers (see NucleotideMonomer) that replace or modify the natural nucleotide at that position. Common modifications include 2'-O-methyl sugars for stability, phosphorothioate backbones for nuclease resistance, or modified bases for binding affinity. Exposed on nucleotide sequence entities to capture the modification pattern of therapeutic oligonucleotides.

- `__typename` (string, optional)
- `baseMonomer` (NucleotideMonomerRef, optional) — The base monomer for the modification.
- `createdAt` (string, optional) — DateTime the modification was created.
- `id` (string, optional) — The ID of the modified nucleotide.
- `nucleotideSequence` (NucleotideSequenceRef, optional) — The nucleotide sequence that this modification belongs to.
- `phosphateMonomer` (NucleotideMonomerRef, optional, nullable) — The phosphate monomer for the modification. If empty, it represents a null phosphate at the 5' end of the sequence.
- `position` (integer, optional) — 0-based index of the modification.
- `sugarMonomer` (NucleotideMonomerRef, optional) — The sugar monomer for the modification.

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### NucleotideMonomerRef

- `__typename` (string, optional)
- `id` (string, optional)

### NucleotideSequenceRef

- `__typename` (string, optional)
- `id` (string, optional)

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "createdAt": "createdAt",
      "id": "id",
      "position": 1
    }
  ],
  "nextToken": "nextToken"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/dna-oligo/dna_oligo_id/modified-nucleotides/items"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/dna-oligo/dna_oligo_id/modified-nucleotides/items';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```