Exon

Exon designates protein-coding sequences within genes that remain in mature messenger RNA after splicing removes intervening sequences called introns, ultimately translated into amino acid sequences comprising functional proteins. Alternative splicing patterns including or excluding specific exons generate protein diversity from single genes.

The biopharmaceutical industry considers exon biology throughout therapeutic development. Gene therapy design requires understanding exon structures when creating expression cassettes. Exon skipping represents a therapeutic strategy for genetic diseases like Duchenne muscular dystrophy, using antisense oligonucleotides inducing ribosome skipping over mutated exons, restoring reading frames and enabling production of partially functional proteins. Genetic testing analyses exonic sequences identifying disease-causing mutations. Companion diagnostics detect exon-specific mutations predicting treatment responses to targeted therapies. Pharmacogenomics examines exonic variants in drug-metabolising enzymes explaining inter-individual response differences. As precision medicine advances, exon biology remains central to molecular diagnostics and therapeutic design.