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Gene Family: 18S ribosomal RNAs (RNA18S)

Also known as : "18S rRNAs", "RNAs, 18S ribosomal"

18S ribosomal RNA: 18 S ribosomal RNA (abbreviated 18S rRNA) is a part of the ribosomal RNA. The S in 18S represents Svedberg units. 18S rRNA is a component of the small eukaryotic ribosomal subunit (40S). 18S rRNA is the structural RNA for the small component of eukaryotic cytoplasmic ribosomes, and thus one of the basic components of all eukaryotic cells. It is the eukaryotic nuclear homologue of 16S ribosomal RNA in Prokaryotes and mitochondria. [Source: Wikipedia]

Genes contained within the family: 5

Approved Symbol Approved Name Previous Symbols Synonyms Chromosome
RNA18S1 RNA, 18S ribosomal 1 13p12 not on reference assembly
RNA18S2 RNA, 18S ribosomal 2 14p12 not on reference assembly
RNA18S3 RNA, 18S ribosomal 3 15p12 not on reference assembly
RNA18S4 RNA, 18S ribosomal 4 21p12 not on reference assembly
RNA18S5 RNA, 18S ribosomal 5 RN18S1 22p12 not on reference assembly


18S rRNAs are processed from 45S pre-RNA. The 45S rRNA genes are present in clusters on 13p12, 14p12, 15p12, 21p12, and 22p12 but due to sequencing difficulties these are not present on the current reference genome. The gene symbols above are representative of one 18s rRNA from one 45S rRNA repeat per cluster for each chromosomal location. The number of repeats within each cluster varies between individuals.

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