Period From
(Myr ago)
To
(Myr ago)
Time range
(Myr)
Origin of miRNA Genes Origin of miRNA gene families
Number Rate Number Rate
p<0.01 p<0.05 p<0.01 p<0.05 p<0.01 p<0.05 p<0.01 p<0.05
1 6.3 0 6.3 122 160 19.4 25.4 72 98 11.4 15.6
2 8.8 6.3 2.5 59 63 23.6 25.2 38 39 12.8 15.6
3 15.7 8.8 6.9 134 122 19.4 17.7 88 81 11.0 11.7
4 20.4 15.7 4.7 89 91 18.9 19.4 92 98 19.5 20.9
5 29.0 20.4 8.6 219 220 25.4 25.6 161 161 18.7 18.7
6 42.6 29.0 13.6 316 317 23.2 23.3 263 261 19.3 19.2
7 92.3 42.6 49.7 169 144 3.4 2.9 121 104 2.4 2.1
The numbers of human miRNA orthologues predicted at significance levels of p<0.01 and p<0.05 were shown for each evolutionary period of birth. The generation rate of miRNA genes per Myr was calculated based on the divergence time estimated by TimeTree [10].
Table 2: Classification of human miRNAs by evolutionary origin.