Mutations in the genes for keratin‐4 and keratin‐13 in Swedish patients with white sponge nevus

Abstract

We describe a novel heterozygous missense mutation in the keratin-4 gene of a Swedish family with white sponge nevus. Our results support the notion that mutations in keratin-4 and keratin-13 are the underlying cause of white sponge nevus.

Keratin 4 regulates the development of human white sponge nevus

“…When chromosomes in recipient cells have homogenous genes with mutation sites, both of their expressions are inhibited, leading to the so‐called cosuppression effect. Additionally, the transgene may be inactivated when homogenous genes are normally expressed …”

“…19 The study by Jorgenson and Levin confirmed the discrete expression of KRT4, and WSN patients from their family fit the rule of autosomal dominant inheritance. 4 There is a 50% chance for the children of WSN patients to develop the same disease. Theoretically, the positive rate for F1 generation of KRT4 transgenic mice should be 50%.…”

“…Additionally, the transgene may be inactivated when homogenous genes are normally expressed. 4 For 2-month-old transgenic mice, the KRT4 protein of the mucosa epithelium exceedingly expressed when assessed by Western blotting and IHC. However, for 3-month-old mice, the entire epithelial lamina showed less staining of KRT4, and the surface and spinous layers were full of hyalocytes and bubble cells.…”

“…However, the lesions grow quickly and may affect all oral mucosa during puberty. 3 WSN shows no sex predilection and familial cases are rare, [4][5][6] which may be due to the irregular penetrance.…”

White sponge nevus in a three‐year‐old boy: A case report

“…White sponge nevus (WSN) is a rare hereditary condition characterized by thickened white spongy plaques of the mucous membranes 1 . It is commonly known as a congenital condition; however, it often does not develop in childhood 2…”