---
layout: rule
id: GORULE:0000006
title: "IEP and HEP usage is restricted to terms from the Biological Process ontology"
type: filter
fail_mode: hard
status: implemented
contact: "go-quality@lists.stanford.edu"
implementations:
  - language: python
    source: https://github.com/biolink/ontobio/blob/master/ontobio/io/qc.py
---
Annotations using the IEA evidence code (GAF column 7; GPAD column 6) must also have Aspect = P (GAF column 9; GPAD does not contain this information directly). 
The reason for this is that IEP and its high throughput equivalent, HEP, evidence codes are used where process involvement is inferred from
the timing or location of expression of a gene, particularly when comparing a gene that is not yet characterized with the timing or
location of expression of genes known to be involved in a particular process. This type of annotation is only suitable with terms from the
Biological Process ontology. For CC annotations that assess the localization of a gene product, IDA should be used.