Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, Xi'an, Shaanxi 710032, PR China.
J Craniomaxillofac Surg. 2012 Jul;40(5):416-20. doi: 10.1016/j.jcms.2011.07.014. Epub 2011 Oct 1.
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.
石骨症是一组遗传性骨疾病。有三种类型的石骨症：常染色体隐性遗传性石骨症（ARO）、常染色体显性遗传性石骨症 II 型（ADO II）和中间常染色体隐性遗传性石骨症（IARO）。ADO II 的患病率约为 1:100,000，而全球报告的 IARO 病例不超过 20 例。我们报告了首例中国 IARO 患者，其 CLCN7 基因存在纯合突变（p.Pro470Leu），以及首例 ADO II 患者，其 CLCN7 基因存在杂合突变（p.Arg286Trp）。除了普遍的骨质硬化外，这两名患者的显著特征是牙齿未萌出且伴有牙根发育不良。我们推测，不同牙齿细胞中的 ClC-7 可能直接有助于牙根发育，ClC-7 的缺陷对牙根发育不良表型可能具有剂量依赖性效应，而牙齿位置也可能会影响因 ClC-7 功能障碍而出现的牙根表型。
