Functional organization and its implication in evolution of the human protein-protein interaction network

BMC Genomics

Table 1 Properties of the PPI network for each temporal group

Temporal group	Approximate group age (MYA)	Gene number in the genome	Gene number in the interaction network	Average interaction degree	Average clustering coefficient	Average Omega
1	990	720	544	29.509	0.212	0.034
2	450	5211	3546	17.399	0.196	0.089
3	360	1929	1093	13.100	0.193	0.096
4	310	2694	1348	10.061	0.180	0.128
5	90	6663	2794	8.623	0.169	0.179
6	50*	1313	205	3.434	0.176	0.168

MYA: million years ago
* Could not be accurately estimated because of our method of assigning temporal groups

ISSN: 1471-2164