'Returns genome-wide data for dataset if available; if not, message is returned.'

def _get_genome_data(self, trans, dataset, dbkey=None):

    rval = None
    data_sources = dataset.get_datasources(trans)
    query_dbkey = dataset.dbkey
    if (query_dbkey == '?'):
        query_dbkey = dbkey
    chroms_info = self.app.genomes.chroms(trans, dbkey=query_dbkey)
    messages_list = [data_source_dict['message'] for data_source_dict in data_sources.values()]
    message = self._get_highest_priority_msg(messages_list)
    if message:
        rval = message
    else:
        source = 'index'
        if isinstance(dataset.datatype, ChromatinInteractions):
            source = 'data'
        data_provider = trans.app.data_provider_registry.get_data_provider(trans, original_dataset=dataset, source=source)
        rval = data_provider.get_genome_data(chroms_info, level=4, detail_cutoff=0, draw_cutoff=0, num_samples=150, interchromosomal=True)
    return rval
