A Novel Mutation in ST14 at a Functionally Significant Amino Acid Residue Expands the Spectrum of Ichthyosis-Hypotrichosis Syndrome

The study identified a novel homozygous p.Asp482Asn mutation in the ST14 gene in a patient with ichthyosis-hypotrichosis syndrome (IHS) from a cohort of 180 ichthyosis patients, expanding the genetic spectrum of this rare disorder. This mutation affected a critical site in the matriptase protein, correlating with specific skin and hair abnormalities, including ichthyosis and hypotrichosis, but without hypohidrosis or ocular and dental anomalies. The findings emphasized the importance of the Asp482 residue and the LDLR-A domains in matriptase activation, contributing to the phenotypic variability of IHS and suggesting that features like follicular atrophoderma and hypohidrosis may vary in severity among patients.