File Format: Signatures (Metadata)

The signatures metadata file format consists of rows corresponding to signatures, with the first column the same as in the signatures data file format.

This file should contain the following columns:

• Signature: The signature name, matching a signature in a signature data file.
• Description: Arbitrary text about the signature. Can be left blank.
• Index: The desired global index of the signature in a listing of all signatures (from all groups of signatures).
• Category Type: The category type of the signature.

For example, the COSMIC signatures metadata file begins as follows

Signature	Description	Index	Category Type
1	Signature 1 is the result of an endogenous mutational process initiated by spontaneous deamination of 5-methylcytosine.	10	SBS_96
2	Signature 2 has been attributed to activity of the AID/APOBEC family of cytidine deaminases. On the basis of similarities in the sequence context of cytosine mutations caused by APOBEC enzymes in experimental systems, a role for APOBEC1, APOBEC3A and/or APOBEC3B in human cancer appears more likely than for other members of the family.	20	SBS_96
...	...	...	...