Marie Unna Hereditary Hypotrichosis: Identification of a U2HR Mutation in the Family from the Original 1925 Report

In 2011, researchers discovered a mutation in the U2HR gene responsible for Marie Unna hereditary hypotrichosis (MUHH) in a family originally described in 1925. The study involved clinical and DNA analysis of one affected individual from the family, who exhibited typical MUHH symptoms and carried the c.3G>A mutation. This mutation was absent in unaffected family members. The findings were consistent with previous discoveries of the same mutation in a North American family and other diverse populations, with a total of 14 distinct mutations identified in 19 MUHH families worldwide. The study's results provided molecular genetic evidence of the cause of MUHH and suggested that sequencing the U2HR gene could be a less invasive diagnostic method than skin biopsy. However, the study's limitation was the investigation of only one affected family member.