Defects in CDSN are a cause of hypotrichosis simplex of the scalp (HTSS) [MIM:146520], also known as hypotrichosis Spanish type. HTSS is an autosomal dominant form of isolated alopecia. Affected individuals have normal hair in early childhood but experience progressive loss of scalp hair beginning in the middle of the first decade and almost complete baldness by the third decade. Defects in CDSN are the cause of peeling skin syndrome type B (BPSS) [MIM:270300], also known as peeling skin syndrome or deciduous skin or keratolysis exfoliativa congenita. BPSS is a genodermatosis characterized by the continuous shedding of the outer layers of the epidermis, associated with pruritus and atopy. It is an ichthyosiform erythroderma characterized by lifelong patchy peeling of the entire skin with onset at birth or shortly thereafter. Several patients have been reported with high IgE levels.Synonyms: S protein