PIK3R4 and dentin dysplasia: By staining serial muscle sections of DD patients for VPS15, CAV3, TFEB, p62, DAPI and neonatal myosin heavy chain (MYH8) we showed that atrophic/vacuolated fibers also displayed upregulation and mislocalization of VPS15, together with increased nuclear TFEB localization and accumulation of p62-positive inclusions (Supplementary Figures S4–S6).