Difference between Exons and Introns

By: Prof. Dr. Fazal Rehman Shamil | Last updated: February 3, 2024

Let me share with you a difference between Exons and Introns.               

AspectExonsIntrons
Introduction·        Exons are found in the coding region of genes.

·        These are present in the mature mRNA transcript.

·        Introns are found in the non-coding region of genes.

·        These are removed during RNA processing, not present in the mature mRNA.

FunctionThese regions code for amino acids, forming the protein-coding sequences.These regions do not code for any amino acids; they are non-coding sequences.
Sequence consistencyMore conserved across related species.Less conserved and may vary between species.
SizeGenerally shorter in size as compared to introns.Generally longer in size as compared to exons.
OriginThought to have originated from the duplication of existing sequences.Thought to have originated from the insertion of non-coding sequences.
Regulatory regionsExons may contain regulatory regions that influence gene expression.Introns generally do not contain regulatory regions related to gene expression.
Splicing SignalsExon-intron boundaries have specific splicing signals (splice sites).Introns contain splicing signals for proper removal during RNA processing.