A Recurrent Intragenic Deletion in the Desmoglein 4 Gene Underlies Localized Autosomal Recessive Hypotrichosis

The study identified a large intragenic deletion in the desmoglein 4 gene (DSG4) as the cause of localized autosomal recessive hypotrichosis (LAH) in two unrelated Pakistani families. LAH was characterized by fragile, sparse hair on the scalp, trunk, and extremities, sparing facial, pubic, and axillary hair. The research involved a family with two affected siblings, revealing a homozygous deletion of exons 5-8 in DSG4, leading to a truncated protein affecting hair follicle differentiation. This mutation was also found in other Pakistani families, suggesting it might have been an ancestral mutation. The findings highlighted the critical role of DSG4 in hair follicle development and the importance of desmosomal function in hair and skin disorders.