1. Research in the region of a gene that contains the code for producing protein.

Each exon codes for a specific portion of the complete protein and exons are separated by introns, long regions of DNA that have no apparent function.

2. The study of a segment of a gene that contains information used in coding for protein synthesis.

Genetic information within genes is discontinuous, split among the exons that encode for messenger RNA and absent from the DNA sequences in between, which are called introns.