---
layout: rule
id: GORULE:0000001
title: "GAF lines are parsed according to GAF 2.2 specifications"
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/gafparser.py
---
Each line of a GAF file is checked that it generally conforms to the GAF 2.2 spec and some
GO specific specifications. The GAF 2.2 spec is here: http://geneontology.org/docs/go-annotation-file-gaf-format-2.2/.

Qualifier, evidence, aspect and DB object columns must be within the list of allowed values
(as per the spec).

Error report (number of errors) in [db_species]-summary.txt & owltools-check.txt (details).