U30 is encoded within the U22 snoRNA host gene (UHG) in mammals and is thought to act as a 2'-O-ribose methylation guide for ribosomal RNA.
Within the context of mammalian cells, U30 is encoded in the U22 small nucleolar RNA host gene (UHG) and plays a role in directing the methylation of ribosomal RNA with 2'-O-ribose.