Interstitial Deletions Generating Fusion Genes

A fusion gene is the physical juxtaposition of two different genes resulting in a structure consisting of the head of one gene and the tail of the other. Gene fusion is often a primary neoplasia-inducing event in leukemias, lymphomas, solid malignancies as well as benign tumors. Knowledge about fusion genes is crucial not only for our understanding of tumorigenesis, but also for the diagnosis, prognostication, and treatment of cancer. Balanced chromosomal rearrangements, in particular translocations and inversions, are the most frequent genetic events leading to the generation of fusion genes. In the present review, we summarize the existing knowledge on chromosome deletions as a mechanism for fusion gene formation. Such deletions are mostly submicroscopic and, hence, not detected by cytogenetic analyses but by array comparative genome hybridization (aCGH) and/or high throughput sequencing (HTS). They are found across the genome in a variety of neoplasias. As tumors are increasingly analyzed using aCGH and HTS, it is likely that more interstitial deletions giving rise to fusion genes will be found, significantly impacting our understanding and treatment of cancer.

Automated summary

Fusion genes are created by the physical joining of two different genes, often as a result of balanced chromosomal rearrangements such as translocations and inversions. Chromosome deletions, which are mostly submicroscopic and not detected by conventional cytogenetic analysis, also play a role in the formation of fusion genes. As tumors are increasingly analyzed using advanced techniques like array comparative genome hybridization (aCGH) and high throughput sequencing (HTS), more interstitial deletions giving rise to fusion genes are expected to be identified, with significant implications for cancer understanding and treatment.