MAPPING OF THE TYROSINE KINASE RECEPTORS TRKA (NTRK1), TRKB (NTRK2) AND TRKC (NTRK3) TO HUMAN-CHROMOSOMES 1Q22, 9Q22 AND 15Q25 BY FLUORESCENCE IN-SITU HYBRIDIZATION

trk (NTRK) genes encode tyrosine kinase transmembrane receptors that a re stimulated by neurotrophins, and are responsible for the transducti on of signals controlling neuropoiesis and neuron survival in the cent ral and peripheral nervous system. trkA gene has earlier been assigned to three different loci on chromosome 1. To resolve these conflicting results, and confirm the localization of trkB and trkC, probes specif ic to each of these related genes were constructed and used in fluores cent in situ hybridization on human metaphase cells. Our results indic ate that trkA, trkB and trkC are located in chromosome bands 1q22, 9q2 2 and 15q25, respectively.