title: A1555G homoplasmic mutation from A1555G heteroplasmic mother with Pendred syndrome.
abstract: Hearing loss (HL) is genetically heterogeneous and can be caused by mutations in multiple gene lesions. Pendred syndrome, caused by mutation of SLC26A4, is one of the common causes of recessive syndromic profound HL. Mitochondrial mutation is another rare cause of genetic HL, resulting in late onset sensorineural HL. Recently, we evaluated a young woman representing bilateral progressive moderate HL with delayed language development, along with her family. Hearing test, temporal bone computed tomography, and genetic evaluation of GJB2, MT-RNR1, SLC26A4 gene mutations were performed on each family member. Her mother was prelingually deaf and displayed enlarged vestibular aqueduct (EVA) along with goiter. Interestingly, subject's mother showed both SLC26A4 mutation and mitochondrial A1555G heteroplasmic mutation at the same time. The sisters did not display EVA or goiter. Although the subject's older sister showed both prelingual deafness and mitochondrial A1555G heteroplasmy, her younger sister showed only A1555G homoplasmy, which suggests A1555G homoplasmy as the genetic cause of hearing loss. This is the first report of HL caused by mitochondrial A1555G homoplasmy from a mother with Pendred syndrome coexistent with A1555G heteroplasmy in the Korean population.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Seoul National University, Seoul, South Korea.
authors.forename: Moo Kyun
authors.initials: MK
authors.lastname: Park
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea; School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, South Korea.
authors.forename: Borum
authors.initials: B
authors.lastname: Sagong
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Soonchunhyang University, Seoul, South Korea.
authors.forename: Jong Dae
authors.initials: JD
authors.lastname: Lee
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea; School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, South Korea.
authors.forename: Seung-Hyun
authors.initials: SH
authors.lastname: Bae
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea; School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, South Korea.
authors.forename: Byeonghyeon
authors.initials: B
authors.lastname: Lee
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea.
authors.forename: Kwang Shik
authors.initials: KS
authors.lastname: Choi
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea; School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, South Korea.
authors.forename: Yeon-Sik
authors.initials: YS
authors.lastname: Choo
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Kyungpook National University, Daegu, South Korea.
authors.forename: Kyu-Yup
authors.initials: KY
authors.lastname: Lee
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea; School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, South Korea. Electronic address: kimuk@knu.ac.kr.
authors.forename: Un-Kyung
authors.initials: UK
authors.lastname: Kim
mesh_terms: D000328:Adult; D000072259:Connexin 26; D017630:Connexins; D004272:DNA, Mitochondrial / Q000235:genetics*; D003638:Deafness / Q000235:genetics; D005260:Female; D006044:Goiter, Nodular / Q000235:genetics*; D034381:Hearing Loss / Q000235:genetics; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D009154:Mutation; D010375:Pedigree; D011859:Radiography; D013701:Temporal Bone / Q000000981:diagnostic imaging; D014723:Vestibular Aqueduct / Q000002:abnormalities
chemical_list: D017630:Connexins; D004272:DNA, Mitochondrial; C000607042:GJB2 protein, human; D000072259:Connexin 26
keywords: A1555G; Hearing loss; Heteroplasmy; MT-RNR1; Pendred syndrome; SLC26A4