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Chemically similar to DNA but a single-stranded molecule. RNA is made up of four chemical bases, known as ‘A’ (adenine), ‘C’ (cytosine), ‘G’ (guanine) and ‘U’ (uracil).

Use in clinical context

RNA is crucial for protein production. As DNA cannot leave the nucleus the relevant sections are transcribed into messenger RNA (mRNA) and transported to the ribosomes where proteins are produced. At the ribosome, transfer RNA (tRNA) facilitates the addition of the correct amino acids to the polypeptide chain which ultimately becomes the protein. The ribosomes themselves are formed of proteins and ribosomal RNA (rRNA).

An additional type of RNA, known as signal recognition particle RNA (SRP RNA), is involved in the control of translation and sorting of membrane and secreted proteins.

By sequencing RNA, it is possible to establish which genes are actively producing proteins and which are not. This can be useful in identifying aberrant gene activity and potential drug targets to inhibit or enhance gene activity to alter gene expression.

In addition to its role in protein production in eukaryotes some viruses have RNA genomes, including influenza, polio, and measles.

Last updated on 30th May, 2019