Massive parallel sequencing of the I AQP5 i coding regions led to identify an I AQP5 i variant in six patients (3.0%), of whom two also carried a heterozygous I CFTR i variant (Table 1). Aquagenic palmoplantar keratoderma (APPK), also known as Aquagenic Wrinkling, is a rare skin disease characterized by transient skin wrinkling with oedema and whitish papules mostly on the palms, rarely on the soles, after water immersion.[1] It is frequently observed in patients with cystic fibrosis (CF)[2] but also occurs sporadically, often in young women. All patients gave their written informed consent to the genetic studies and had an in-depth I CFTR i gene study, leading to unmask CF in one and a CFTR-RD in 13. [Extracted from the article]