Table 1.

Four categories of evidence codes used in GO and their meanings

Experimental	Computational	Author	Curatorial
EXP: inferred from experiment	ISS: inferred from sequence or structural similarity	TAS: traceable author statement	IC: inferred by curator
IDA: inferred from direct assay	ISO: inferred from sequence orthology	NAS: non-traceable author statement	ND: no biological data available
IPI: inferred from physical interaction	ISA: inferred from sequence alignment
IMP: inferred from mutant phenotype	ISM: inferred from sequence model
IGI: inferred from genetic interaction	IGC: inferred from genomic context
IEP: inferred from expression pattern	IBA: inferred from biological aspect of ancestor
	IBD: inferred from biological aspect of descendant
	IKR: inferred from key residues
	IRD: inferred from rapid divergence
	RCA: inferred from reviewed computational analysis
	IEA: inferred from electronic annotation