Table 1.

Selective forces operating on GenAge functional categories.

GenAge category	n	Ka/Ks	p-value higha	p-value lowa	n in 4-way comparisonsb	Ka/Ks in hominids	Ka/Ks in murids	Homo AA diff.c	Pan AA diff.c
apoptosis	65	0.13	1	2.8E−09	43	0.082	0.10	14	15
calcium	6	0.18	0.75	0.25	3	0.29	0.17	2	0
metabolism cell cycle control	42	0.13	1	7.5E−07	26	0.057	0.11	10	9
DNA condensation	28	0.22	0.67	0.33	8	0.32	0.16	6	9
DNA repair	38	0.25	0.24	0.79	16	0.17	0.17	9	11
DNA	15	0.24	0.42	0.58	7	0.079	0.14	4	2
replication energy apparatus	19	0.12	1	5.1E−05	12	0.13	0.082	7	6
growth and development	66	0.14	1	5.9E−10	44	0.13	0.13	37	17
other	47	0.17	1	2.9E−3	27	0.17	0.14	12	16
redox and oxidative	23	0.18	0.92	0.11	13	0.10	0.071	4	3
regulation signaling	52	0.13	1	1.9E−08	27	0.13	0.097	15	16
stress response	31	0.14	1	2.4E−4	14	0.10	0.087	4	5
transcriptional regulation	39	0.15	1	2.6E−3	22	0.062	0.084	3	7

^aThis binomial probability is not used to directly reject the null hypothesis of a given GenAge category not undergoing rapid (probability high) or slow (probability low) evolution but provides a metric to identify categories potentially undergoing rapid or slow evolution. The test statistic threshold was set at 0.001 (see Materials and Methods).

^bK_a/K_s ratios in hominids are based on 4-way alignments and hence are expected to be different from K_a/K_s ratios based on only chimpanzee and human alignments, as described (Chimpanzee Sequencing and Analysis Consortium, 2005).

^cAmino acid differences (AA diff.) represent amino acid changes estimated to have occurred specifically in the human (Homo) or chimpanzee (Pan) lineage.