Identification of 736T>A mutation of lipase H in Japanese siblings with autosomal recessive woolly hair.

Woolly hair is characterized by fine and tightly curled hair. It has recently been revealed that both LPAR6 and lipase H (LIPH) mutations cause autosomal recessive woolly hair (ARWH)/hypotrichosis. This notion has provided critical evidence to the concept that LPA6 activation by LIPH-catalyzed lipid mediator lysophosphatidic acid has a key role in regulation of hair follicle development. Very recently, novel mutations in exon 6, homozygous 736T>A and compound heterozygous 736T>A and 742C>A have been identified in Japanese ARWH/hypotrichosis patients. Here, we report on siblings (a 7-year-old Japanese girl and her 5-year-old brother) both showing woolly hair. Determination of their genomic sequence showed presence of a homozygous 736T>A transition in exon 6 of the LIPH gene changing cysteine at position 246 to serine, without any mutation in the LPAR6 gene. Additionally, the same mutation was found in one out of a 100 alleles of Japanese healthy controls and identified homozygously in three out of four other Japanese sporadic cases with woolly hair. Collectively, it has been suggested that 736T>A transition is highly specific and common in ARWH/hypotrichosis of Japanese origin.