Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Stiftingtalstraße 24; A-8010 Graz, Austria.
Brain. 2011 Jun;134(Pt 6):1839-52. doi: 10.1093/brain/awr076. Epub 2011 May 15.
To identify the disease-causing gene responsible for an autosomal dominantly inherited Charcot-Marie-Tooth neuropathy subtype in a family excluded for mutations in the common Charcot-Marie-Tooth genes, we used array-based sequence capture to simultaneously analyse the disease-linked protein coding exome at chromosome 14q32. A missense mutation in fibulin-5, encoding a widely expressed constituent of the extracellular matrix that has an essential role in elastic fibre assembly and has been shown to cause cutis laxa, was detected as the only novel non-synonymous sequence variant within the disease interval. Screening of 112 index probands with unclassified Charcot-Marie-Tooth neuropathies detected two further fibulin-5 missense mutations in two families with Charcot-Marie-Tooth disease and hyperextensible skin. Since fibulin-5 mutations have been described in patients with age-related macular degeneration, an additional 300 probands with exudative age-related macular degeneration were included in this study. Two further fibulin-5 missense mutations were identified in six patients. A mild to severe peripheral neuropathy was detected in the majority of patients with age-related macular degeneration carrying mutations in fibulin-5. This study identifies fibulin-5 as a gene involved in Charcot-Marie-Tooth neuropathies and reveals heterozygous fibulin-5 mutations in 2% of our patients with age-related macular degeneration. Furthermore, it adumbrates a new syndrome by linking concurrent pathologic alterations affecting peripheral nerves, eyes and skin to mutations in the fibulin-5 gene.
为了鉴定一个家族中常染色体显性遗传的腓骨肌萎缩症亚型的致病基因,该家族排除了常见的腓骨肌萎缩症基因的突变,我们使用基于阵列的序列捕获技术,同时分析染色体 14q32 上与疾病相关的蛋白编码外显子。在疾病相关区间内,发现了一个纤维连接蛋白 5 的错义突变,该蛋白广泛表达于细胞外基质中,对弹性纤维的组装至关重要,并且已经被证明可以导致皮肤松弛症。在未分类的腓骨肌萎缩症神经病变的 112 名索引患者中进行筛查,在两个具有腓骨肌萎缩症和皮肤过度伸展的家族中,发现了另外两个纤维连接蛋白 5 的错义突变。由于纤维连接蛋白 5 的突变已在年龄相关性黄斑变性患者中描述,本研究还纳入了另外 300 名有渗出性年龄相关性黄斑变性的患者。在 6 名患者中发现了另外两个纤维连接蛋白 5 的错义突变。携带纤维连接蛋白 5 突变的年龄相关性黄斑变性患者中,大多数都出现了轻度至重度的周围神经病变。本研究确定纤维连接蛋白 5 是一种参与腓骨肌萎缩症神经病变的基因,并在 2%的年龄相关性黄斑变性患者中发现了杂合的纤维连接蛋白 5 突变。此外,它通过将影响外周神经、眼睛和皮肤的同时发生的病理改变与纤维连接蛋白 5 基因的突变联系起来,描绘了一种新的综合征。