ALK and neoplasm: In addition, our findings that AlkY1355S and AlkF1251L do not drive uncontrolled proliferation in the Drosophila brain support earlier reports in mouse and zebrafish models (Borenäs et al., 2021; Cazes et al., 2014; Fadeev et al., 2016; Ono et al., 2019), where mutation of Alk alone is insufficient to drive spontaneous tumor development.