The arrangement of the genes on our chromosomes could be viewed as a very inefficient one. Throughout many genes, protein coding-portions (exons) are interrupted several times by very large introns. For lack of known functions attributed to them, these introns could be considered a nuisance. In fact, in order to produce a functional protein from a specific gene, the cell must remove and discard introns via splicing and this removal requires energy.

However, recent findings have led to the surprising finding that for some genes, introns may be part of the mechanisms to insure adequate protein production. The Yeast Intron Removal Project plans to address the role that introns, and combinations of introns, play in gene expression.

The approach is simple and consists in replacing intron-containing genes with their intronless versions using Saccharomyces cerevisiae as an experimental system due to its small quantity of introns. The impact of such substitutions on cell growth, fitness and gene expression is assessed for each gene individually and for specific combinations of genes (pathways). This approach should uncover novel and unsuspected ways for introns to participate in the life of a cell.