What are introns?

Introns are defined as non-coding sequences within a gene that are transcribed into pre-mRNA but are subsequently removed during RNA processing. This process takes place during the maturation of mRNA before it is translated into protein. Introns vary in length and number among different genes, and their removal allows for the joining of exons, which are the coding sequences that actually dictate the amino acid sequence of a protein.

The presence of introns is thought to play a role in gene regulation and alternative splicing, where different combinations of exons can be joined together to create multiple protein isoforms from a single gene. This adds to the complexity and functionality of the proteins that can be produced by an organism.