There are several versions of rRNA that have been used in the literature. snoDB defaults to the snoRNABase annotation:

• 5.8S U13369.1:6623-6779
• 18S X03205.1
• 28S U13369.1:7935-12969

5.8S rRNA

All 5.8S versions are identical.

18S rRNA

There are 3 major versions of 18S, but there are only small changes that do not affect the modified positions. Here are some articles or references that have used the different versions:

• X03205.1 snoRNABase, snoRNA Atlas
• NR_003286 snOPY, Gumienny et al. (2017).
• NR_145820.1 Incarnato et al. (2017), Zhu et al. (2017).

28S rRNA

There are 2 major versions of 28S, for which the modified positions are not identical. U13369.1:7935-12969 is the one used in snoRNABase while NR_003287.4 is the "Human reference rRNA" sequence used to obtain the structure of rRNA. Here are some articles or references that have used the different versions:

• U13369.1 :7935-12969 snoRNABase, snoRNA Atlas, snOPY, Gumienny et al. (2017)
• NR_003287.4 Incarnato et al. (2017), Zhu et al. (2017)