Genomic sequencing of IP associated SCC has also noted mutations in lysine methyltransferase 2A (KMT2D), cyclin-dependent kinase inhibitor 2A (CDKN2A), tumor protein 53 (TP53), phosphodiesterase 4D interacting protein (PDE4DIP), and neurofibromin 1 (NF1) [47]. Here, PDE4DIP is linked to incontinentia pigmenti.