DNA Diagnostics by Capillary Electrophoresis
DNA Diagnostics by Capillary Electrophoresis
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DOI：
10.1002/chin.200805278
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发表时间：
2008-01
期刊：
影响因子：
--
通讯作者：
K. Klepárník;P. Boček
中科院分区：
文献类型：
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作者：
K. Klepárník;P. Boček
早期分子方法在临床遗传诊断经常被认为是明确和明确的。人们认为，至少在理论上，现代分子生物学的力量足以提供成功的基因分析。这甚至可能导致基于单一基因单一疾病概念的治疗。然而，越来越清楚的是，仅靠遗传方法不足以令人满意地描述和诊断复杂的表型。单基因疾病，如杜氏肌营养不良症、血友病或镰状细胞性贫血，占人类疾病总负担不到2%。其余的是多基因疾病，必须在细胞或有机体的大背景下看待。尽管单个分子遗传标记的检测显然不能完全取代复杂的诊断方法，但可靠的高通量分析技术和敏感的分子诊断工具的重要性和必要性是毋庸置疑的。每一个生物体在其一生中都会积累DNA物质的变化。这些变化以多种方式发生：(i)复制过程中的复制错误；（ii）由环境（辐射、外源性化学物质、毒素、激素甚至饮食）引起的变化；（iii）自发DNA损伤（去嘌呤化、去嘧啶化和脱胺化），导致核苷酸碱基丢失或碱基修复特性的改变。当谈到DNA突变或多态性时，我们指的是基因组中核苷酸序列的稳定变化，这些变化是由于DNA物质的损伤或改变而没有得到纠正。虽然多态性代表了至少1%的人群中存在的DNA序列的变化，并且不被认为是有害的，但突变不太常见（少于1%的人群），并且经常导致疾病或增加患疾病的风险。在一个特定位点上的其他形式的基因被称为等位基因。在个体的特定位点上的相同或不同的等位基因分别称为纯合子或杂合子。2
Early molecular methods in clinical genetic diagnostics were frequently regarded as unambiguous and definitive. The power of modern molecular biology was seen as sufficient for providing, in theory at least, a successful genetic analysis. This could even lead to a therapy based on a single genesingle disease concept. However, it has become increasingly clear that genetic approaches alone are insufficient for the satisfactory description and diagnostics of complex phenotypes. Monogenic diseases such as Duchenne muscular dystrophy, hemophilia, or sickle cell anemia represent less than 2% of the total human disease burden. The rest are polygenic diseases and must be viewed in the larger context of a cell or an organism. Even though it is clear that detection of individual molecular genetic markers cannot completely replace a complex diagnostic approach, the importance and necessity for reliable high-throughput analytical technologies and sensitive tools for molecular diagnostics is unquestionable. 1Every living organism accumulates changes to its DNA material during its life span. These changes occur in a number of ways:(i) copying errors during replication;(ii) changes caused by the environment (radiation, exogenous chemicals, toxins, hormones, or even diet);(iii) spontaneous DNA damage (depurination, depyrimidination, and deamination), resulting in loss of a nucleotide base or a change in the basepairing properties of a base. When speaking about DNA mutations or polymorphisms, we mean only the stable changes in the nucleotide sequence of the genome resulting from damage or alterations to the DNA material that have not been corrected. While polymorphism represents changes in the DNA sequence that are present in at least 1% of the population and are not considered harmful, mutations are less common (less than 1% of population) and frequently result in disease or an increased risk for developing a disease. Alternative forms of genes at a particular locus are called alleles. Identical or different alleles at a particular locus in an individual are referred to as homozygous or heterozygous, respectively. 2