A newly identified missense mutation of the HR gene is associated with a novel, unusual phenotype of Marie Unna Hereditary Hypotrichosis 1 including limb deformities.

Marie Unna Hereditary Hypotrichosis 1 (MUHH1; OMIM 146550), a rare monogenic condition characterized by the development of sparse, twisted hair or complete hair loss, is the consequence of mutations located in the hairless (HR) gene. We have identified a 68-year-old Hungarian woman affected by alopecia universalis and limb deformities of all four extremities. Direct sequencing of the coding regions of the HR gene revealed a novel missense mutation in the third exon of the HR gene (c.974G/A, p.Gly325Asp). The affected family member carried the mutation in a heterozygous form, while the only available, clinically unaffected family member (the son of the patient) and the unrelated controls carried the wild type sequence. The association between the presence of HR gene mutations and the development of alopecia is well-established, however, further studies are needed to elucidate the putative role of this novel HR mutation in the development of limb deformities.