fusion gene
A hybrid gene created by chromosomal rearrangements that joins portions of two different genes, often driving cancer development.
Full Definition
Fusion genes result from chromosomal translocations, inversions, or deletions that bring together sequences from two normally separate genes. These molecular events can create novel oncoproteins with altered function, constitutive activation, or aberrant cellular localization. In precision oncology, fusion genes serve as both diagnostic markers and therapeutic targets. Examples include BCR-ABL1 in chronic myeloid leukemia, EML4-ALK in lung cancer, and TMPRSS2-ERG in prostate cancer. Detection methods include fluorescence in situ hybridization (FISH), reverse transcription-PCR, and next-generation sequencing.
Usage
Usage note: Gene names in fusions are typically joined by hyphens (e.g., BCR-ABL1, EML4-ALK).
In Context
- "The patient's tumor harbored an EML4-ALK fusion gene, predicting crizotinib sensitivity." — Molecular diagnostic report
- "RNA sequencing identified a novel fusion gene involving the RET kinase." — Research publication