Congenital Hair Loss Disorders: Rare, But Not Too Rare

The 2011 document reviews congenital hair loss disorders (CHLD) and their genetic causes, focusing on the structure of the hair follicle (HF) and the hair cycle. It explains that mutations in genes expressed in the HF can lead to CHLD, presenting as hair shaft anomalies like woolly hair and monilethrix. Specifically, it notes that in Japanese populations, congenital woolly hair/hypotrichosis is often due to mutations in the LIPH gene, which is involved in lipid signaling and hair growth. The review also discusses keratin diseases caused by mutations in keratin genes and other disorders resulting from mutations in desmosomal components, classical cadherins, and other genes like HR, CDSN, APCDD1, and potentially RPL21. The importance of understanding the genetic basis of CHLD is emphasized for improving knowledge of HF development and hair growth, which could lead to treatments for more common hair loss disorders. Dermatologists are encouraged to familiarize themselves with the clinical characteristics and molecular basis of CHLD. The research was supported by grants from Japanese institutions.