Diagnosis and treatment of isolated autosomal recessive woolly hair/hypotrichosis

Isolated autosomal recessive woolly hair/hypotrichosis (ARWH, OMIM:278150) is a rare congenital disorder marked by sparse, tightly curled "woolly" hair. ARWH is associated with mutations in <i>LIPH</i>, <i>LPAR6</i>/P2RY5, <i>KRT25</i>, and <i>C3ORF52</i>, with <i>LIPH</i> and <i>LPAR6</i> as the primary causative genes. Mutation prevalence varies globally: in Japan, founder mutations c.736 T > A (p.Cys246Ser) and c.742C > A (p.His248Asn) in <i>LIPH</i> are predominant; Pakistan reports a recurrent <i>LIPH</i> exon 5 deletion (c.659_660del); Russia's Volga-Ural region has an exon 4 deletion (c.527_628del); and 12 out of 19 Chinese ARWH cases are linked to <i>LIPH</i> c.742C > A. <i>LPAR6</i> mutations are sporadic, with rare occurrences in Pakistani families and two Chinese cases. <i>KRT25</i> mutations include the Russian founder variant c.712G > T (p.Val238Leu) and the Pakistani c.950 T > C (p.Leu317Pro). <i>C3ORF52</i> mutations are newly identified and reported only in two U. S. cases. No definitive treatment exists, but minoxidil, gentamicin, regenerative therapies, and plant-derived compounds show potential. Regional mutation patterns highlight genetic founder effects and population-specific variations in ARWH pathogenesis.