VPS33A and Hermansky-Pudlak syndrome: While this mouse model has been considered a model of the Hermansky–Pudlak syndrome (HPS; OMIM PS203300), no genes found to cause HPS in humans have been linked to HOPS/CORVET complex functions and neither our patients nor the VPS33A R498W patients (Dursun et al, 2017; Kondo et al, 2017; Pavlova et al, 2019) display symptoms of HPS such as hypopigmentation and bleeding diathesis.