Esposito Teresa, Piluso Giulio, Saracino Dario, Uccello Rossella, Schettino Carla, Dato Clemente, Capaldo Guglielmo, Giugliano Teresa, Varriale Bruno, Paolisso Giuseppe, Di Iorio Giuseppe, Melone Mariarosa A B
Laboratory of Molecular Genetics, Department of Experimental Medicine section F.Bottazzi, Second University of Naples, Naples, Italy.
Services Dietetics, Department of Experimental Medicine section F.Bottazzi, Second University of Naples, Naples, Italy.
J Neurochem. 2015 Dec;135(6):1123-8. doi: 10.1111/jnc.13396. Epub 2015 Nov 12.
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic condition caused by dominant loss-of-function mutations of the tumor suppressor gene NF1 that encodes neurofibromin, a negative regulator of RAS activity. Mutation analysis of NF1 located at 17q11.2 has been hampered by the large size of the gene, the high rate of new mutations, the lack of mutational clustering, and the presence of several homologous loci. To date, about 80% of the reported NF1 mutations are predicted to result in protein truncation, but very few studies have correlated the causative NF1 mutation with its effect at the protein level. We evaluated a novel diagnostic method to detect truncated forms of neurofibromin in a large cohort of unrelated subjects suspected of having NF1, according to the NIH consensus criteria. Western blot analysis was carried out on protein extracts from patients' leukocytes to highlight the possible presence of altered neurofibromin as a result of mutations in NF1. Truncated neurofibromin was identified in 274/336 patients (81%), confirming the usefulness and reproducibility of the proposed diagnostic approach. Our methodology can be routinely applied in the diagnostic setting, thanks to its simplicity and reliability. Combined with molecular approaches, it may increase the accuracy and efficiency of NF1 genetic testing. We evaluated a novel diagnostic method to detect truncated forms of neurofibromin in patients fulfilling the clinical criteria for Neurofibromatosis 1. Western blot analysis identified truncated neurofibromin in 274/336 patients (81%). Our results indicate that the proposed technique is cheap and reliable, and could ideally be performed as a preliminary biochemical screening before molecular analysis of the NF1 gene.
1型神经纤维瘤病（NF1）是一种常染色体显性遗传病，由肿瘤抑制基因NF1的功能丧失性显性突变引起，该基因编码神经纤维瘤蛋白，它是RAS活性的负调节因子。位于17q11.2的NF1基因的突变分析因该基因的巨大规模、新突变的高发生率、缺乏突变聚集以及存在几个同源基因座而受到阻碍。迄今为止，所报道的NF1突变中约80%预计会导致蛋白质截短，但很少有研究将致病性NF1突变与其在蛋白质水平的影响相关联。我们根据美国国立卫生研究院（NIH）的共识标准，评估了一种新的诊断方法，用于在一大群疑似患有NF1的无关受试者中检测神经纤维瘤蛋白的截短形式。对患者白细胞的蛋白质提取物进行了蛋白质印迹分析，以突出由于NF1突变可能存在的改变的神经纤维瘤蛋白。在274/336名患者（81%）中鉴定出截短的神经纤维瘤蛋白，证实了所提出的诊断方法的有效性和可重复性。由于其简单性和可靠性，我们的方法可常规应用于诊断环境。与分子方法相结合，它可能会提高NF1基因检测的准确性和效率。我们评估了一种新的诊断方法，用于在符合1型神经纤维瘤病临床标准的患者中检测神经纤维瘤蛋白的截短形式。蛋白质印迹分析在274/336名患者（81%）中鉴定出截短的神经纤维瘤蛋白。我们的结果表明，所提出的技术便宜且可靠，理想情况下可在对NF1基因进行分子分析之前作为初步生化筛查进行。
