阵列比较基因组杂交（CGH阵列），用于检测基因拷贝数变异的
Summary
阵列CGH为基因拷贝数变异的检测已经取代G-带状核型分析。本文介绍了技术及其在诊断服务实验室的应用。
Abstract
Array CGH for the detection of genomic copy number variants has replaced G-banded karyotype analysis. This paper describes the technology and its application in a clinical diagnostic service laboratory. DNA extracted from a patient’s sample (blood, saliva or other tissue types) is labeled with a fluorochrome (either cyanine 5 or cyanine 3). A reference DNA sample is labeled with the opposite fluorochrome. There follows a cleanup step to remove unincorporated nucleotides before the labeled DNAs are mixed and resuspended in a hybridization buffer and applied to an array comprising ~60,000 oligonucleotide probes from loci across the genome, with high probe density in clinically important areas. Following hybridization, the arrays are washed, then scanned and the resulting images are analyzed to measure the red and green fluorescence for each probe. Software is used to assess the quality of each probe measurement, calculate the ratio of red to green fluorescence and detect potential copy number variants.
Introduction
它已被公知多年了缺失或染色体片段的额外拷贝会导致智力障碍，异形和congentical畸形，并在某些情况下会导致遗传综合征1。不过，可用，直到2000年代中期的全基因组检测这些变化的唯一技术是G-带状染色体分析，其中有四周5-10Mb的分辨率，这取决于不平衡的地区和性质，并不能检测异常染色体其中材料已经被替换的区域，从一个不同的染色体具有相同的带型。如荧光原位杂交和多重连接特异性探针扩增辅助细胞遗传学技术已经可以为特定位点的审讯，在涉嫌的具体综合征失衡的情况下，但它不是直到引进阵列比较基因组杂交（CGH阵列）进入常规临床诊断service 2-5的全基因组检测的拷贝数变异（CNV的），在大大提高分辨率（通常大约120KB）成为可能。临床服务工作一起研究的研究表明，CNV的某些区域是在正常人群6-7普遍，而其他的CNV，先前不可检测的，与neurodisabilities如孤独症和癫痫8-11相关联。
本文描述的协议，用于在我们的英国国民健康服务（NHS）临床诊断实验室;我们用新颖的杂交策略，批量测试和机器人，以减少在这个国家资助的服务成本。
之前下面详述的协议，高品质的DNA应该提取从适当的起始材料，通常血液，培养的细胞或组织样品。分光光度法，可用于测量浓度（应> 50纳克/ UL），并检查260：280比例的吸光度（应BË1.8-2.0）。凝胶电泳可用于检查该DNA是高分子量无显著降解。
此协议是专为那些每个标签使用自动化液体处理机器人运行96个样品更高的吞吐量实验室。但是，它也可以适用于低吞吐量的实验室没有自动化。
Protocol
Representative Results
Discussion
阵列CGH不会检测平衡重排或倍体异常，如三倍体。此外，低水平的马赛克的不平衡可能不会被检测到。然而，阵列CGH对CNV检测比G-带状染色体分析，它已经取代了许多细胞遗传学实验室更高的分辨率。因此，目前的黄金标准的全基因组CNV检测。它可能是由下一代测序技术在未来被替换，但目前，它们的成本和技术复杂性与使用短相关读出用于检测CNV的意思，这还不是一个很好的适合临床使用。
…Divulgazioni
The authors have nothing to disclose.
Acknowledgements
The authors have no acknowledgements.
Materials
| Name of Material/ Equipment | Company | Catalog Number | Comments/Description |
| CGH microarray 8 x 60K | Agilent | G4126 | |
| Array CGH wash buffers | Agilent | 5188-5226 | |
| Array CGH hybridisation buffer | Agilent | 5188-5380 | |
| Minelute purification kit | Qiagen | 28006 | |
| Array CGH labelling kit | Enzo | ENZ-42672-0000 |
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