MITF and Werner syndrome: To date, ∼400 mutations including missense/nonsense mutations, frameshift mutations, insertions/deletions, and copy number variants (CNVs) have been identified in genes associated with WS (The Human Gene Mutation Database1), with most variants in genes PAX3, SOX10, and MITF (Chen et al., 2010; Pingault et al., 2010; Song et al., 2016).