SAM/BAM

Provides a format for storing next-generation sequencing read data

When sequencing DNA, the raw sequences that come off a machine — the “reads” — are aligned to a reference genome. Then, thee reads are traditionally stored in one of two file types: a human-readable text file of sequence data called SAM (Sequence Alignment/Map), and its binary counterpart, BAM (Binary Alignment/Map).

Maintained by the GA4GH Large Scale Genomics (LSG) Work Stream, SAM and BAM are used throughout the genomics and health field to store genomic sequences. The highly-compressed version of BAM, CRAM, is transitioning into the field’s preferred file format for storing sequencing reads, as it reduces file size and thus storage costs.

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Benefits

  • Provides a common format to store genomic sequence read data

Target users

Researchers, and data custodians

Image summary: Learn how the formats SAM/BAM and CRAM store aligned sequencing reads — a foundational step when working with genomic data.

Community resources

Dive deeper into this product! The genomics community has traditionally used SAM and BAM to store sequencing reads. In essence, SAM is a TAB-delimited text format consisting of an optional header section and an alignment section that aligns the sequences to a reference genome. Each alignment line has eleven mandatory fields for essential alignment information, such as mapping position. BAM converts this information into binary code, reducing the file size.


Title

Info

Repeat

Day

Time

Duration

This group meets to discuss all GA4GH File Formats maintained by the Large-Scale Genomics Work Stream: SAM/BAM/CRAM and VCF/BCF.

Every Two Months
Tuesday
00:00 UTC
1 Hour

This group meets to discuss all GA4GH File Formats maintained by the Large-Scale Genomics Work Stream: SAM/BAM/CRAM and VCF/BCF.

Every Two Months
Tuesday
20:00 UTC
1 Hour

Date

Version

22 Aug 2022

Title

Related Driver Projects and Organisations

Don't see your name? Get in touch:

  • Robert Davies
    Wellcome Sanger Institute (WSI)
  • Richard Durbin
    University of Cambridge
  • Yosr Hamdi
    Institut Pasteur de Tunis
  • Michael Hoffman
    Princess Margaret Cancer Centre
  • John Marshall
    University of Glasgow
  • Martin Pollard
    Wellcome Sanger Institute (WSI)

News, events, and more

Catch up with all news and articles associated with SAM/BAM.

8 Jul 2021
GA4GH standards in a global learning health system
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