Highly Prevalent LIPH Founder Mutations Causing Autosomal Recessive Woolly Hair/Hypotrichosis in Japan and the Genotype/Phenotype Correlations

The study analyzed 14 unrelated Japanese families with autosomal recessive woolly hair/hypotrichosis (ARWH) and identified two prevalent LIPH mutations, c.736T>A and c.742C>A, as causative. Homozygous c.742C>A mutations were linked to severe hypotrichosis, while homozygous c.736T>A mutations resulted in milder forms. Screening of 819 healthy Japanese controls showed allele frequencies of 0.87% for c.736T>A and 0.16% for c.742C>A, with carrier rates of 1.7% and 0.32%, respectively. The study highlighted the importance of genetic screening for accurate diagnosis and suggested that mutation patterns might influence the severity of hypotrichosis in ARWH.