Berger A, Bruschek M, Grethen C, Sperl W, Kofler B
Children's Hospital, General Hospital, Salzburg, Austria.
Diagn Mol Pathol. 2001 Mar;10(1):55-9. doi: 10.1097/00019606-200103000-00009.
Analysis of the mitochondrial DNA (mtDNA) is an important part in the diagnosis of mitochondrial disorders. Besides point mutations and deletions in the mitochondrial genome a reduction in the amount of mtDNA molecules (mtDNA depletion) can also be the reason for mitochondrial defects. The DNA stability in clinical samples is essential for proper performance and interpretation of DNA based diagnosis. The stability of mtDNA was compared with that of nuclear DNA under poor handling and storage conditions. Fresh and thawed muscle tissue specimens were kept at different temperatures for a certain period of time before DNA isolation. Quantitative Southern blot analysis revealed a time-dependent decrease in the amount of mtDNA compared with nuclear DNA in thawed tissue specimens. Therefore, the current study demonstrates that proper specimen storage is a critical issue in quantitative mtDNA analysis and that poor handling and storage of tissue may mimic a severe mtDNA depletion.
线粒体DNA（mtDNA）分析是线粒体疾病诊断的重要组成部分。除了线粒体基因组中的点突变和缺失外，mtDNA分子数量的减少（mtDNA耗竭）也可能是线粒体缺陷的原因。临床样本中的DNA稳定性对于基于DNA的诊断的正确执行和解释至关重要。在处理和储存条件不佳的情况下，对mtDNA和核DNA的稳定性进行了比较。新鲜和解冻的肌肉组织标本在DNA分离前于不同温度下保存一定时间。定量Southern印迹分析显示，与解冻组织标本中的核DNA相比，mtDNA数量呈时间依赖性下降。因此，当前研究表明，合适的样本储存是定量mtDNA分析中的关键问题，并且组织处理和储存不当可能会模拟严重的mtDNA耗竭。
