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When a DNA variant changes a coding codon to a stop codon. This results in a shorter, often non-functional protein.

Use in clinical context

Nonsense variants can have severe implications on the production of the protein that the gene provides instructions for. These variants introduce stop codons into a gene prematurely, stopping translation and resulting in a short mRNA and short protein. Usually this causes incorrect protein function, with resulting phenotypic effects for the individual. Nonsense variants can cause some rare conditions, including cystic fibrosis and beta-thalassaemia.

Last updated on 16th November, 2021