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Summary of Changes for BEL v2.2


Summary of Changes for BEL v2.1


Summary of Changes for BEL v2.0

These additions and modifications enhance the BEL language by providing new representation capability (e.g., DNA and RNA variants, protein cleavage fragments, cellular location of abundances) and enabling the use of external vocabularies (post-translational modifications, activities).


  • Now represents sequence variants at DNA, RNA, and protein levels.
  • Now represents multiple substitutions within the same gene/RNA/protein
  • New BEL abundance modifier functionvariant("") / var("") is used for most variant types,

replacing substitution() / sub() and truncation() / trunc().

Human Genome Variation Society (HGVS) nomenclature adopted to describe variants

Dunnen and Antonarakis, 2000

within the var("") modifier function, expanding supported types of variation to include insertions,

deletions, duplications as well as non-specific variants.

Protein Cleavage Fragments

  • New abundance modifier function fragment() / frag() to be used within protein abundances

to specify protein fragments based on amino acid sequence range.

Post-Translational Protein Modifications

  • The proteinModification() / pmod() abundance modifier function can now

use external vocabularies (e.g., PSI-MOD)

for modification types, enabling users to add types without requiring a language change.

  • Now multiple pmod() expressions can be used within a protein abundance.

Translocations and Cellular Location

Activity Functions

Regulates Relationship

  • New causal relationship regulates to represent cases where A is reported to affect B, but it cannot be determined if A increases or decreases B.

BEL Script Format Changes

  • Citation annotation requirement removed for Name field
  • Citation annotation DOI and URL added as accepted types
  • BEL Script Evidence Annotation renamed to Support
  • BEL version set in document header