Table 1. A sample of organisms in the Riley dataset with their respective protein, domain and gold domain sizes.

Organism	Number of proteins	Number of unique domains	Number of gold domains
All	11,403	12,455	642
Drosophila melanogaster	3,777	5,454	387
Saccharomyces cerevisiae	3,476	4,949	392
Caenorhabditis elegans	2,233	3,746	289
Homo sapiens	799	1,816	209
Schizosaccharomyces pombe	10	15	7
Bacillus subtilis	9	10	3

A gold domain is a domain that is involved in at least one GDDI. These GDDIs were obtained from [6], and are domain-pairs whose interaction has been confirmed in iPfam [16] from PDB crystal structures.