MITF and neoplasm: Recently, using single-cell RNA sequencing, we and others have demonstrated high transcriptional heterogeneity and distinct cell states in the primary tumour and MRD, including states with low-to-no expression of pigmentation lineage markers such as melanocyte inducing transcription factor (MITF)-independent populations (Baron et al., 2020; Ennen et al., 2015; Gerber et al., 2017; Rambow et al., 2018; Tirosh et al., 2016; Travnickova et al., 2019).