title: Report of two Chinese patients suffering from CLCN7-related osteopetrosis and root dysplasia.
abstract: Osteopetrosis is a group of genetic bone disorders. There are three types of osteopetrosis: autosomal recessive osteopetrosis (ARO), autosomal dominant osteopetrosis type II (ADO II), and intermediate autosomal recessive osteopetrosis (IARO). The prevalence of ADO II is about 1:100,000, while no more than 20 cases of IARO have been reported worldwide. We present the first Chinese IARO patient with a novel homozygous variant in CLCN7 gene (p. Pro470Leu) and an ADO II patient with a heterozygous variant in CLCN7 gene (p. Arg286Trp). In addition to general osteosclerosis, the striking features of these two patients are unerupted teeth with root dysplasia. We speculate that ClC-7 in different tooth cells may contribute directly to the root development, the defect of ClC-7 may have a dose dependent effect on the phenotype of root dysplasia, and the tooth position may also affect the root phenotype with dysfunctional ClC-7.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, Xi'an, Shaanxi 710032, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xue
authors.forename: Weiguang
authors.initials: W
authors.lastname: Wang
authors.forename: Tianqiu
authors.initials: T
authors.lastname: Mao
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Duan
mesh_terms: D000328:Adult; D001120:Arginine / Q000235:genetics; D015519:Bone Density / Q000235:genetics; D002681:China; D018118:Chloride Channels / Q000235:genetics*; D063169:Dentofacial Deformities / Q000235:genetics; D005808:Genes, Recessive / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007930:Leucine / Q000235:genetics; D008297:Male; D010019:Osteomyelitis / Q000175:diagnosis; D010022:Osteopetrosis / Q000235:genetics*; D010026:Osteosclerosis / Q000235:genetics; D010641:Phenotype; D017354:Point Mutation / Q000235:genetics; D011392:Proline / Q000235:genetics; D014071:Tooth Abnormalities / Q000235:genetics; D014092:Tooth Root / Q000002:abnormalities*; D014097:Tooth, Unerupted / Q000175:diagnosis; D014364:Tryptophan / Q000235:genetics
chemical_list: C097540:CLCN7 protein, human; D018118:Chloride Channels; D014364:Tryptophan; D001120:Arginine; D011392:Proline; D007930:Leucine