MAPPING OF THE GENE FOR THE TYROSINE KINASE-ITK TO A REGION OF CONSERVED SYNTENY BETWEEN MOUSE CHROMOSOME-11 AND HUMAN-CHROMOSOME-5Q

The protein-tyrosine kinase gene Itk is expressed preferentially in T lymphoid cells of the mouse and is induced by IL-2. A related gene, Bt k, is expressed in the murine B lymphoid and myeloid lineages. Because mutations in Btk and the corresponding human gene are associated with X-linked immunodeficiency syndromes, it was of interest to map Itk an d its human counterpart. By Southern blot analysis of DNA from the pro geny of two multilocus crosses, murine Itk was mapped to Chromosome 11 . By fluorescence in situ hybridization, human ITK was mapped to 5q32- q33. Murine Itk and its human homologue lie within regions of conserve d synteny that include several growth factor and growth factor recepto r genes. This region in humans is frequently deleted in the myelodyspl astic syndrome, suggesting possible involvement of ITK in this disorde r. (C) 1994 Academic Press, Inc.