SBS90 · · COSMIC v91

Mutational profile

Mutational profile using the conventional 96 mutation type classification. This classification is based on the six substitution subtypes: C>A, C>G, C>T, T>A, T>C, and T>G (all substitutions are referred to by the pyrimidine of the mutated Watson—Crick base pair). Show more

Further, each of the substitutions is examined by incorporating information on the bases immediately 5’ and 3’ to each mutated base generating 96 possible mutation types (6 types of substitution x 4 types of 5’ base x 4 types of 3’ base). Mutational signatures are displayed and reported based on the observed trinucleotide frequency of the human genome, i.e., representing the relative proportions of mutations generated by each signature based on the actual trinucleotide frequencies of the reference human genome version GRCh37.


Proposed aetiology

Duocarmycin exposure.

Comments

Very strong sequence context enrichment, with a preference for thymines up to 4bp 3’ of mutated thymines.


Tissue distribution

Found in breast and oesophagus metastatic cancers treated with duocarmycin-based antibody–drug conjugates.



Transcriptional strand bias

SBS90 shows strong transcriptional strand bias for T>A substitutions with more mutated A than T bases on the untranscribed strands of genes compatible with damage to adenine.

tbs patterns