Department of Medical Biotechnology and Laboratory Science/Graduate Institute of Medical Biotechnology, Taoyuan, Taiwan.
Ann N Y Acad Sci. 2010 Jul;1201:13-20. doi: 10.1111/j.1749-6632.2010.05626.x.
Human mitochondrial DNA (mtDNA) encodes 13 polypeptides essential for oxidative phosphorylation. Because of the unique features of "replicative segregation" and "threshold expression" of mtDNA genetics, identification of homoplasmy versus heteroplasmy status is critical. Results from various detection methods may lead to different interpretations on formation or outcome of mtDNA mutations, such as the conclusion of somatic mutation versus genetic drift in cancers. Denaturing high-performance liquid chromatography (DHPLC) and pyrosequencing (PSQ) have recently been employed to confirm the presence of heteroplasmy of mtDNA because of their high sensitivity in detecting heteroplasmic mutations compared with direct sequencing. Moreover, PSQ has superior ability in quantifying percentage of heteroplasmy. However, there could be disagreement between these two techniques and several issues specific for mtDNA should be taken into consideration. Particularly, DHPLC analysis should be more prone to be interfered by nuclear mitochondrial sequences (Numts), if it is coamplified with mtDNA, than PSQ analysis.
人类线粒体 DNA（mtDNA）编码了 13 种对氧化磷酸化至关重要的多肽。由于 mtDNA 遗传学具有独特的“复制分离”和“阈值表达”特征，因此确定同质性与异质性状态至关重要。各种检测方法的结果可能会导致对 mtDNA 突变形成或结果的不同解释，例如癌症中体细胞突变与遗传漂变的结论。变性高效液相色谱（DHPLC）和焦磷酸测序（PSQ）最近被用于确认 mtDNA 异质性的存在，因为与直接测序相比，它们在检测异质突变方面具有更高的灵敏度。此外，PSQ 在定量异质性百分比方面具有更高的能力。然而，这两种技术之间可能存在差异，并且应该考虑到 mtDNA 特有的几个问题。特别是，如果 DHPLC 分析与 mtDNA 一起扩增，那么它比 PSQ 分析更容易受到核线粒体序列（Numts）的干扰。
