NTRK3 and severe combined immunodeficiency: While there have not been any comprehensive GEM models described to date, both ETV6-NTRK3 as well as the non-canonical fusion gene EML4-NTRK3 have been shown to be able to transform murine NIH3T3 fibroblasts, which successfully engrafted s.c. in severe combined immunodeficiency disease (SCID) and NOD SCID gamma (NSG) immunocompromised mice to result in tumors with IFS-like histomorphology [124,125].