When attempting to use the json_api renderer with Django 1.10rc1 I'm getting a strange error about field.related not being set. It appears this was a private attribute that was deprecated in 1.8 and has finally been removed.
Partial trace
lib/python3.5/site-packages/rest_framework_json_api/utils.py", line 194, in get_related_resource_type
relation_model = parent_model_relation.field.related.model
AttributeError: 'ForeignKey' object has no attribute 'related'