def create_edge(vertex_1, vertex_2, edge_type, strand, edge_dict, run_info):
    """ Creates a novel edge and adds it to the edge data structure. """
    run_info.edge += 1
    new_ID = run_info.edge
    new_edge = {'edge_ID': new_ID,
                'v1': vertex_1,
                'v2': vertex_2,
                'edge_type': edge_type,
                'strand': strand }
    edge_dict[(vertex_1, vertex_2, edge_type)] = new_edge

    return new_edge