Incontinentia pigmenti (IP) (Bloch-Sulzberger-syndrome, OMIM #308300) is a rare hereditary multisystemic neuroectodermal disorder caused by pathogenic variants in the IKBKG gene (formerly known as NEMO (nuclear factor-kappa B (NF-kB) essential modulator)) on X chromosome. Here, IKBKG is linked to incontinentia pigmenti.