Using CRISPR/Cas9-mediated genome editing, we generated LYST-deficient NK cells that reproduced the cellular phenotype reported for patients with CHS with mutations in the ARM/HEAT domain of LYST, including defective cytotoxicity, impaired granzyme delivery to target cells, enlarged lytic granules, and altered integrity of endolysosomal compartments.33 Here, LYST is linked to Chediak-Higashi syndrome.