Mutations in the CDSN gene cause peeling skin disease and hypotrichosis simplex of the scalp

Peeling skin disease is a rare genodermatosis characterized by superficial exfoliation or peeling of the skin. Peeling skin disease is caused by biallelic mutations in CDSN as an autosomal recessive trait. Monoallelic mutations in CDSN have also been described in an autosomal dominant inherited genodermatosis: hypotrichosis simplex of the scalp. This disease is characterized by progressive hair loss of the scalp with onset after early childhood. Clinical data were obtained from a patient with lifelong generalized skin peeling and both his parents. The patient's parents did not suffer from skin peeling, but the mother had a history of thin scalp hair since early childhood. Mutation analysis in the patient showed compound heterozygous mutations in exon 2 of CDSN, a nonsense mutation c.598C>T (p.[Gln200*]), previously associated with hypotrichosis simplex of the scalp, and a frame‐shift mutation c.164_167dup (p.[Thr57Profs*6]), previously described in peeling skin disease. The p.(Gln200*) mutation was also found in the mother of the proband. Our study strengthens the previously established link between mutations in CDSN to peeling skin disease and hypotrichosis simplex of the scalp.