# 1. Introduction

### What is a KRA?

The Korea Sequence Read Archive (KRA) is a repository that collects, stores, and manages high- throughput sequencing data produced across diverse biological and biomedical research fields. KRA serves as the central archive for **raw sequencing data** generated by next-generation sequencing (NGS) platforms, ensuring data traceability, accessibility, and long-term preservation.

KRA accepts a broad range of experiment types, including:

* Whole-genome sequencing (WGS) and whole-exome sequencing (WES)
* Transcriptome sequencing (RNA-seq) and epigenome assays (ChIP-seq, ATAC-seq, etc.)
* Metagenome and microbiome sequencing
* Single-cell and spatial transcriptomic sequencing

All submissions to KRA must include both metadata and corresponding data files, such as raw sequence reads and secondary data files.\
The repository ensures interoperability with other K-BDS databases (KNA, KVar, KEA) and international archives ([INSDC](https://www.insdc.org/)) by adopting standardized metadata formats, accession systems, and controlled vocabularies. See the [About](https://kbds.re.kr/KRA/about) page for more details. 

***

### **Key Features of KRA**

#### Comprehensive sequencing data management

KRA primarily archives **raw sequencing data (e.g., FASTQ)** generated by various high-throughput sequencing platforms.

#### Multi-platform and multi-omics coverage

Data generated from various sequencing technologies — such as Illumina, Oxford Nanopore, PacBio, and BGI — is accepted. Supported experiment types span genomics, transcriptomics, epigenomics, metagenomics, and single-cell omics.

#### Integration within the K-BDS ecosystem

All KRA records are directly linked to their corresponding BioProject and BioSample entries, allowing users to trace data provenance and experimental context.\
KRA also interoperates with other specialized repositories such as KNA (nucleotide sequences), KVar (genomic variants), and KEA (functional genomics data).

#### Metadata standardization and validation

KRA enforces submission according to standardized metadata schemas aligned with international repositories (INSDC SRA metadata model).\
Automated validation and controlled vocabularies ensure data consistency, FAIR compliance (Findable, Accessible, Interoperable, Reusable), and high-quality archiving.

#### Open access and data reuse

Registered datasets receive permanent accession numbers and can be accessed through web interfaces, APIs, or data download tools, enabling reuse for secondary analyses, benchmarking, and meta-studies.

***

## Cite

**To describe data deposition in your manuscript, use the following sentence:**

\
\&#xNAN;*The raw sequence data reported in this paper have been deposited in the Korea Sequence Read Archive (KRA) under accession number(s) KAPxxxxxx and are publicly accessible at* [*https://kbds.re.kr/KRA*](https://kbds.re.kr/KRA)*.*

> Contact KRA staff for assistance at <mark style="color:blue;"><kra@kribb.re.kr></mark>

This guide was last updated on *2026.03.01*.


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