Recent observations indicate that alternative splicing is a common way for eukaryotes to expand their repertoire of gene functions. Studies indicate that approximately 50 percent of human genes exhibit alternative splicing and approximately 15 percent of disease-causing mutations involve aberrant alternative splicing. Different tissues show remarkably different frequencies of alternative splicing, with the brain accounting for approximately 18 percent of such events [Xu et al. (2002). Nucl. Acids Res. 30:3754–3766].

Why might some tissues engage in more alternative splicing than others?

Key Concepts

Alternative Splicing

Alternative splicing is a regulatory mechanism in eukaryotic gene expression that allows a single gene to produce multiple mRNA variants by including or excluding certain exons. This process increases the diversity of proteins that can be generated from a single gene, enabling cells to adapt their functions based on specific developmental stages or environmental conditions.

Tissue-Specific Gene Expression

Tissue-specific gene expression refers to the phenomenon where certain genes are expressed at different levels or are activated in specific tissues. This selective expression is crucial for the specialization of cells, allowing different tissues to perform unique functions, which can influence the frequency and type of alternative splicing events that occur in those tissues.

Functional Adaptation

Functional adaptation in biology refers to the process by which organisms or tissues evolve to better suit their environment or specific roles. In the context of alternative splicing, certain tissues may require a greater variety of protein functions to meet their unique physiological demands, leading to higher rates of alternative splicing to generate the necessary protein diversity.