Gene fusion refers to a biological event where two separate genes are fused together to form a hybrid gene. This can result from chromosomal rearrangements, such as translocations, deletions, or inversions, and can lead to the creation of novel proteins with altered or combined functions. Gene fusions are often found in cancer cells and have been shown to play a role in tumorigenesis and disease progression. Studying gene fusion events can provide insight into the underlying molecular mechanisms of diseases and may lead to the development of novel diagnostic and therapeutic strategies.