Ontology references >1

[helenp]

@diekhans from discussion on meta data call 04/06/2015 - allow ontology terms to be >1 - some annotations cannot be captured in as single ontology term e.g. mixed x and y tissue, or when disease stages and diseases are conflated in a single annotation and do not resolve cleanly to a single ontology term.

[nlwashington]

can this be accomplished with an array in the relevant schema?

[mbaudis]

We have this format in preparation at https://github.com/ga4gh/metadata-team/blob/master/avro-playground/metadata_redo.avdl:

  /**
  Phenotypes for this individual.
  */
  array<OntologyTerm> phenotypes = [];

This is a working doc for collecting comments on different items; opinions are welcome!

[david4096]

The biocharacteristics message adopts this approach. https://github.com/ga4gh/ga4gh-schemas/pull/836