Gene tagging is a molecular biology technique that involves attaching a small molecule or a protein to a gene of interest to track the gene's expression, location, and function within the cell or organism. There are several synonyms for gene tagging, including gene fusion, gene labeling, genetic marking, and genetic tracking. The use of these different terms is often context-dependent and may vary depending on the specific research question or application. Gene tagging has numerous applications in modern biology, including identifying disease-causing genes, understanding gene regulation and cellular signaling pathways, and developing novel therapies for genetic disorders.