Abstract:
Tooth agenesis in the reduction of tooth number which includes hypodontia, oligodontia and anodontia is caused by disturbances and gene mutations that occur during odontogenesis. To date, several genetic mutations that unlock the causes of non-syndromic tooth agenesis are being discovered; these have been associated with certain illnesses because tooth development involves the interaction of several genes for tooth epithelium and mesenchyme odontogenesis. Mutation of candidate genes PAX9 and MSX1 have been identified as the main causes of hypodontia and oligodontia; meanwhile, AXIN2 mutation is associated with anodontia. Previous study using animal models reported that PAX9-deficient knockout mice exhibit missing molars due to an arrest of tooth development at the bud stage. PAX9 frameshift, missense and nonsense mutations are reported to be responsible; however, the most severe condition showed by the phenotype is caused by haploinsufficiency. This suggests that PAX9 is dosage-sensitive. Understanding the mechanism of genetic mutations will benefit clinicians and human geneticists in future alternative treatment investigations.
摘要:
牙齿发育不全在牙齿数量减少中,包括牙体发育不全,少牙和无牙是由牙本质形成过程中发生的干扰和基因突变引起的。迄今为止,目前正在发现几种解释非综合征性牙齿发育不全原因的基因突变;这些突变与某些疾病有关,因为牙齿发育涉及牙齿上皮和间充质牙本质形成的几种基因的相互作用。候选基因PAX9和MSX1的突变已被确定为低牙体和少牙体的主要原因;同时,AXIN2突变与牙齿缺失有关。先前使用动物模型的研究报告说,缺乏PAX9的基因敲除小鼠由于在芽阶段牙齿发育停滞而表现出磨牙缺失。PAX9移码,据报道,错义和无义突变是负责任的;然而,表型显示的最严重的情况是由单倍体功能不全引起的。这表明PAX9是剂量敏感的。了解基因突变的机制将使临床医生和人类遗传学家在未来的替代治疗研究中受益。