From: Evolution of ribonuclease H genes in prokaryotes to avoid inheritance of redundant genes
Kingdom | Type | No. of species | No. of RNase H genes | ||
---|---|---|---|---|---|
1 | 2 | 3 | |||
Archaea | RNase HI | 9 | 6 | 3 | 0 |
 | RNase HII | 27 | 27 | 0 | 0 |
 | RNase HIII | 1 | 1 | 0 | 0 |
Bacteria | RNase HI | 210 | 173 | 32 | 5 |
 | RNase HII | 220 | 219 | 1 | 0 |
 | RNase HIII | 40 | 40 | 0 | 0 |