Background Desmosomes are complex cell junction structures that connect intermediate filaments providing strong cell-to-cell adhesion in tissues exposed to mechanical stress. Objectives To identify causal variants in individuals with woolly hair and skin fragility of unknown genetic cause. Methods This research was conducted using whole-genome sequencing, whole-exome sequencing, clinical phenotyping, haplotype analysis, single-cell RNA sequencing data analysis, immunofluorescence microscopy and transmission electron microscopy. Results We identified homozygous predicted loss-of-function tuftelin-1 (TUFT1) variants in nine individuals, from three families, with woolly hair and skin fragility. One donor splice-site variant, c.60+1G>A, was present in two families, while a frameshift variant, p.Gln189Asnfs*49, was found in the third family. Haplotype analysis showed the c.60+1G>A substitution to be a founder variant in the Irish population that likely arose approximately 20 generations ago. Human and mouse single-cell RNA sequencing data showed TUFT1 expression to be enriched in the hair dermal sheath and keratinocytes. TUFT1 expression was highly correlated with genes encoding desmosomal components implicated in diseases with phenotypes that overlap with the cohort presented here. Immunofluorescence showed tuftelin-1 to be mainly localized to the peripheral cell membranes of keratinocytes in normal skin. Skin samples from individuals with TUFT1 variants showed markedly reduced immunoreactivity for tuftelin-1, with a loss of the keratinocyte cell membrane labelling. Light microscopy revealed keratinocyte adhesion, mild hyperkeratosis and areas of superficial peeling. Transmission electron microscopy showed panepidermal acantholysis with widening of intercellular spaces throughout the epidermis and desmosomal detachment through the inner plaques. Conclusions Biallelic loss-of-function TUFT1 variants cause a new autosomal recessive skin/hair disorder characterized by woolly hair texture and early-onset skin fragility. Tuftelin-1 has a role in desmosomal integrity and function.

Epidermolysis bullosa acquisita is a highly uncommon condition in the paediatric population. This article describes three children with this disease, different clinical presentation and management. It also reviews the most relevant articles on this topic.

Un varón de 4 años, sin antecedentes personales ni familiares de relevancia, fue llevado al Servicio de Dermatología por presentar lesiones lineales congénitas en el hemicuerpo izquierdo.En el examen físico se evidenciabanmicropápulas hipopigmentadas de distribución lineal,las cuales seguían las líneas de Blaschko y comprometían el hemitronco, el glúteo y el miembro inferior izquierdo.

BackgroundDystrophic epidermolysis bullosa (DEB) is a subtype of an inherited skin disorder characterized by skin and mucosal fragility due to collagen VII (COL7A1) gene mutations. Esophageal strictures leading to chronic dysphagia and acute episodes are well recognized complications within this subtype. Sloughing of esophageal mucosa and the treatment of this emergency have heretofore received limited attention in the EB literature.MethodsWe retrospectively reviewed the electronic medical records of the patients who had an acute episode of sloughing of the esophageal lining between 2008 and 2021 and extracted the information regarding their clinical presentation and management.ResultsSix patients out of 210 with recessive DEB severe (RDEB‐S) (n = 4), RDEB intermediate (RDEB‐I) (n = 1) and dominant DEB (DDEB) (n = 1) were identified. The mean age at the time of the episode was 2.7 years. All patients had early‐onset severe gastroesophageal reflux. Clinically, they presented with a coughing episode (n = 6), hematemesis (n = 6), vomiting (n = 6), and choking (n = 3), followed by coughing up a string like tissue of variable length, part of the esophageal mucosal lining. Four patients recovered with medical management only, two patients required gastrostomy insertions for feeding due to severe persistent dysphagia and one also required a Nissen's fundoplication to manage severe reflux. One patient had aspiration pneumonia.ConclusionsSloughing of varying lengths of segments of the esophagus is an emergency. The lining coughed up needs to be cut at the mouth not pulled and the emergency services called immediately for urgent assessment and management. Expert multidisciplinary care is needed to manage this rare but serious condition.