Zhang Yingying, Zhou Dong, Yang Tianhua
Department of Neurology, West China Hospital, Sichuan University, Chengdu, China.
Medicine (Baltimore). 2019 Jan;98(4):e14122. doi: 10.1097/MD.0000000000014122.
Pantothenate kinase-associated neurodegeneration (PKAN), also called Hallervorden-Spatz Syndrome (HSS), is a rare neurodegeneration with brain iron accumulation from pantothenate kinase 2 gene (PANK2) mutation characterized as extrapyramidal symptoms. However, few studies involving PKAN patients were reported in China. This study was conducted to identify the genetic mutations in a Chinese boy with PKAN, and to review all PANK2 mutations reported in Chinese cases with PKAN.
We reported a 23-year-old Chinese boy with PKAN, exhibiting difficulty in writing and manipulation using right hand with slow progression for 12 years. He spoke with a severe stutter when he was 15 years old.
Considering results of magnetic resonance images, brain computed tomography and medical history, the case was suspected to be related to genetic factors.
Whole exome sequencing was arranged, and the mutations were identified in his parents' genome.
In the present study, whole exome sequencing revealed 2 novel mutations (c.1696C > G in exon 7 and c.1160_c.1161insG in exon3) of the PANK2 gene in the proband. c.1696C > G and c.1160_c.1161insG, respectively, were confirmed in his father and mother. We also reviewed 14 different PANK2 mutations, most of which were missense type in Chinese cases. Those mutations did not show apparent hotspots, but exon 3 and 4 were frequently involved.
Two novel compound heterozygous mutations were identified and considered to be pathogenic in PKAN patients. This review of the reports indicated that atypical PKAN is the more common phenotype in China and no apparent genotype-phenotype correlation was found.
泛酸激酶相关神经变性(PKAN),也称为哈勒沃登 - 施帕茨综合征(HSS),是一种罕见的神经变性疾病,因泛酸激酶2基因(PANK2)突变导致脑铁蓄积,其特征为锥体外系症状。然而,中国报道的涉及PKAN患者的研究较少。本研究旨在鉴定一名患有PKAN的中国男孩的基因突变,并回顾中国PKAN病例中报道的所有PANK2突变。
我们报告了一名23岁患有PKAN的中国男孩,其右手书写和操作困难,病程长达12年且进展缓慢。他15岁时说话严重口吃。
综合磁共振成像、脑计算机断层扫描结果及病史,怀疑该病例与遗传因素有关。
安排了全外显子组测序,并在其父母基因组中鉴定出突变。
在本研究中,全外显子组测序揭示了先证者PANK2基因的2个新突变(外显子7中的c.1696C>G和外显子3中的c.1160_c.1161insG)。其父亲和母亲分别证实携带c.1696C>G和c.1160_c.1161insG突变。我们还回顾了14种不同的PANK2突变,在中国病例中大多数为错义型。这些突变未显示明显的热点区域,但外显子3和4频繁受累。
鉴定出2个新的复合杂合突变,被认为在PKAN患者中具有致病性。对这些报告的回顾表明,非典型PKAN在中国是更常见的表型,且未发现明显的基因型 - 表型相关性。