Case ReportA novel homozygous HOXB1 mutation in a Turkish family with hereditary congenital facial paresis

Hereditary congenital facial paresis (HCFP) is characterized by isolated dysfunction of the facial nerve (CN VII) due to congenital cranial dysinnervation disorders. HCFP has genetic heterogeneity and HOXB1 is the first identified gene. We report the clinical, radiologic and molecular investigations of three patients admitted for HCFP in a large consanguineous Turkish family. High-throughput sequencing and Sanger sequencing of all patients revealed a novel homozygous mutation p.Arg230Trp (c.688C>T) within the HOXB1 gene. The report of the mutation brings the total number of HOXB1 mutations identified in HCFP to four. The results of this study emphasize that in individuals with congenital facial palsy accompanied by hearing loss and dysmorphic facial features, HOXB1 mutation causing HCFP should be kept in mind.