Gao Zhijie, Xie Hua, Jiang Qian, Wu Nan, Chen Xiaoli, Chen Qian
Department of Neurology, Affiliated Children's Hospital of Capital Institute of Pediatrics, No. 2, Yabao Road, Chaoyang District, Beijing, 100020, China.
Department of Medical Genetics, Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics, Beijing, 100020, China.
BMC Med Genet. 2018 Feb 8;19(1):21. doi: 10.1186/s12881-018-0535-7.
Neuronal ceroid lipofuscinoses (NCLs) are one of the most frequent childhood-onset neurodegenerative pathologies characterized by seizures, progressive cognitive decline, motor impairment and loss of vision. For the past two decades, more than 430 variants in 13 candidate genes have been identified in the affected patients. Most of the variants were almost exclusively reported in Western patients, and very little clinical and genetic information was available for Chinese patients.
We report a Chinese boy whose clinical phenotypes were suspected to be NCL, including intractable epilepsy, cognitive and motor decline and progressive vision loss. Using targeted next-generation sequencing, two novel null variants in CLN8 (c.298C > T, p.Gln100Ter; c.551G > A, p.Trp184Ter) were detected in this patient in trans model. These two variants were interpreted as pathogenic according to the variant guidelines of the American College of Medical Genetics and Genomics.
This is the first case report of NCL due to CLN8 variants in China. Our findings expand the variant diversity of CLN8 and demonstrate the tremendous diagnosis value of targeted next-generation sequencing for pediatric NCLs.
神经元蜡样脂褐质沉积症(NCLs)是最常见的儿童期起病的神经退行性疾病之一,其特征为癫痫发作、进行性认知衰退、运动障碍和视力丧失。在过去二十年中,已在受影响患者中鉴定出13个候选基因中的430多个变异体。大多数变异体几乎仅在西方患者中报道,而关于中国患者的临床和遗传信息非常少。
我们报告一名中国男孩,其临床表型疑似为NCL,包括难治性癫痫、认知和运动功能衰退以及进行性视力丧失。使用靶向二代测序,在该患者中检测到CLN8基因的两个新型无义变异体(c.298C>T,p.Gln100Ter;c.551G>A,p.Trp184Ter),呈反式模式。根据美国医学遗传学与基因组学学会的变异体指南,这两个变异体被判定为致病性变异。
这是中国首例因CLN8变异导致NCL的病例报告。我们的研究结果扩展了CLN8变异体的多样性,并证明了靶向二代测序对儿童NCLs具有巨大的诊断价值。