应用微阵列比较基因组杂交技术和SNP分型定位Ⅰ型神经纤维瘤病脊柱侧凸的修饰基因

The mechanism of scoliosis in neurofibromatosis type 1（NF1） remains unclear. The result of large sample family study demonstrated whether NF1 patients suffered from scoliosis was up to modifying gene（MG）. But the locus of MG in genome and which genes are MGs remain unclear. In this research project, array-based comparative genomic hybridization will be used to determine DNA copy number changes in the bone of NF1 patients with scoliosis. Candidate MG will be chosen around the region of DNA copy number changes. According to genotype data from International HapMap project, the key single nucleotide polymorphisms (SNPs) of candidate MG will be selected, and all selected SNPs will be genotyped. The positive SNPs will be determined by the association analysis, and primarily ascertainment of MG will be made. The expression of candidate MG will be tested, and the relationship between the positive SNPs and the expression of candidate MG will be found out by statistical analysis to validate and ascertain MG. The primarily molecular mechanism of scoliosis in NF1 will be found, which will provide new ideas and theory basis for early screening and control of scoliosis in NF1.

Ⅰ型神经纤维瘤病（NF1）患者发生脊柱侧凸的确切机制尚未阐明，大样本的家系研究证明NF1患者是否发生脊柱侧凸由修饰基因（modifying gene，MG）决定，但是MG在基因组中的位置尚未确定，MG具体是哪些基因也未能明确。本课题将采用比较基因组杂交技术明确NF1脊柱侧凸患者骨组织中的DNA扩增或缺失区域，在该区域中选取候选MG，根据国际人类基因组单体型图计划提供的基因型数据选取候选MG的SNP位点，进行SNP位点基因型检测，通过关联分析确定阳性SNP位点，初步确定MG，并检测候选MG表达水平，通过统计分析明确阳性SNP位点与候选MG表达水平的关系，进一步验证确定MG，初步揭示NF1患者发生脊柱侧凸的分子机制，为NF1脊柱侧凸的早期筛查与防治开拓新思路和提供理论依据。

1型神经纤维瘤病（NF1）患者发生脊柱侧凸的确切机制尚未阐明，大样本的家系研究证明NF1患者是否发生脊柱侧凸由修饰基因（modifying gene，MG）决定，但是MG在基因组中的位置尚未确定，MG具体是哪些基因也未能明确。本课题采用全基因组外显子测序检测NF1患者血液标本，按照有无侧凸进行分组，对比两组患者基因突变情况，并与正常人进行对照，发现2个InDel突变位点：在5号染色体的167881026位置，正常碱基AGGT突变为A，对应的基因名称：WW and C2 domain containing 1（WWC1）；在19号染色体的14200896位置，正常碱基C突变为CG，对应的基因名称：sterile alpha motif domain containing 1（SAMD1）。经文献检索，WWC1编码的蛋白为KIBRA，主要在脑和肾表达，与人类记忆、阿尔茨海默病、肾脏肿瘤、前列腺癌、乳腺癌关系密切，尚未有相关研究证明与骨骼肌肉系统相关；而SAMD1编码的蛋白为Atherin，与动脉粥样硬化斑块关系密切，而且Atherin在机体内广泛表达，可能系导致1型神经纤维瘤病患者发生脊柱侧凸的MG。该发现初步揭示了NF1患者发生脊柱侧凸的分子机制，为NF1脊柱侧凸的早期筛查与防治开拓新思路和提供理论依据。