HGNC recommendations for gene fusions

Dear readers and collaborators of the Atlas of Genetics and Cytogenetics in Oncology and Hematology,

For more than sixty years the presence of chromosomal translocations has been a hallmark of cancer. The fusion genes were first discovered in cancer cells in the 1980s and began to be identified at the breakpoints of chromosomal rearrangements, particularly important were recurrent balanced translocations in Burkitt's lymphoma (BL) and chronic myeloid leukemia (CML). Since the first descriptions, more and more fusion genes have been described in hematological malignancies and solid tumors. Cytogenetics has a clear nomenclature indicated in the ISCN 2020. However, until now there has not been a standardization indicating the genes involved in fusions and, in most of the publications, the symbols for the genes in question are listed separated by a dash (-) or a forward slash (\/).


With the advent of Next Generation Sequencing more than 30,000 fusion genes have been identified and there is a need for a unique and standardized way to indicate fusion genes. Recently, HGNC concluded that it was necessary to find an alternative nomenclature to replace the use of a dash (-) or a forward slash (\/). HGNC has worked with the scientific community to determine a new, unique and instantly recognizable separator, a double colon (::), to be used in the description of fusion genes, and advocates the use in all databases and articles describing fusion genes.

As editors of the Atlas of Genetics and Cytogenetics in Oncology and Hematology, we support the HGNC recommendations by the HGVS and ISCN, and by the following resources: WHO Tumor Classification, COSMIC, OMIM, Mitelman Database of Chromosome Aberrations and Gene Fusions in Cancer, and the Tumor fusion gene data portal. We encourage all our readers and collaborators to use and publish this form of annotation to describe fusion genes in all future communications to avoid confusion, using an unambiguous scientific nomenclature.

Download Bruford et al, Leukemia 2021