45S ribosomal DNA (rDNA) arrays, or clusters, are present on human chromosomes 13, 14, 15, 21 and 22, designated RNR1 through RNR5, respectively. Each cluster consists of multiple 45S rDNA repeat units that vary in number among individuals and chromosomes, with total diploid copy number estimates ranging from 60 to >800 repeat units in a human genome. The 45S rDNA repeat unit encodes a 45S rRNA precursor, transcribed by RNA polymerase I, which is processed to form the 18S, 5.8S and 28S rRNAs. This locus represents a likely pseudogene and copy of the 18S ribosomal RNA, part of an incomplete rDNA repeat unit on chromosome 21. [provided by RefSeq, May 2017]
GeneCards Summary for RNA18SP5 Gene
RNA18SP5 (RNA, 18S Ribosomal Pseudogene 5) is a Pseudogene.