The human tyrosine kinase gene (FER) maps to chromosome 5 and is deleted in myeloid leukemias with a del(5q).

A novel member of the SRC tyrosine kinase gene family was recently isolated and characterized (Hao et al., 1989). This FES/FPS-related gene, named FER, lacks the transmembrane and extracellular domains which characterize tyrosine kinases with receptor function. Expression of FER in a wide range of cell types indicates a general role in intracellular signalling or differentiation processes. We have now mapped FER to chromosome 5q14----q23 using in situ hybridization techniques and suggest a more precise location within bands 5q21----q22. This region lies adjacent to a complex domain of growth factors and receptors, many involved in regulation of haematopoiesis. FER maps within a critical segment frequently deleted from chromosome 5 in patients with acute myeloid leukemia or myelodysplastic syndromes and was shown to be deleted in two such patients. It also maps close to the familial polyposis coli locus at 5q22.