Effects of formalin fixation, paraffin embedding, and time of storage on DNA preservation in brain tissue:: A BrainNet Europe study
Effects of formalin fixation, paraffin embedding, and time of storage on DNA preservation in brain tissue:: A BrainNet Europe study
复制标题
DOI：
10.1111/j.1750-3639.2007.00073.x
复制
发表时间：
2007-07-01
期刊：
影响因子：
6.4
通讯作者：
Kretzschmar, Hans
中科院分区：
文献类型：
--
作者：
Ferrer, Isidre;Armstrong, Judith;Kretzschmar, Hans
脑标本库和脑库中保存了大量的脑组织，但福尔马林固定的脑组织和脑库中保存多年的石蜡块是否适合于回顾性遗传学研究，目前还知之甚少。进行该研究的目的是：（i）比较储存不同时期的冷冻、福尔马林固定和石蜡包埋组织中的DNA保存;（ii）研究储存不同时期的冷冻、福尔马林固定和石蜡包埋材料中的点突变和三联体扩增，并使用不同的固定液;（iii）比较不同的方法以优化从保存欠佳的脑组织中提取DNA和扩增DNA。DNA保存适用于在-80 ℃下储存数年的样品的遗传研究。福尔马林固定的石蜡包埋组织不如冷冻组织，但在许多情况下确实产生了足够的结果，这取决于固定液的类型和包埋前的固定时间。在福尔马林中长时间固定很少产生有用的DNA。在朊病毒病的样本中也得到了类似的结果。通过在冷冻材料、石蜡块和福尔马林固定的组织中使用Qiagen试剂盒（Qiagen DNA Micro）获得最佳结果。Genomiphi（TM）和TaKaRa Ex Taq（TM）方法也在石蜡块和福尔马林固定的样品中进行了测定，但成功率有限。
There is a large amount of tissue stored in brain collections and brain banks, but little is known about whether formalin-fixed tissues and paraffin blocks stored for years in brain banks are suitable for the retrospective genetic studies. The study was carried out in order to: (i) compare DNA preservation in frozen, formalin-fixed and paraffin-embedded tissues stored for different periods; (ii) study point mutations and triplet expansions in frozen, formalin-fixed and paraffin-embedded material stored for variable periods, and using different fixative solutions; (iii) compare different methods to optimize DNA extraction and DNA amplification from suboptimally preserved brain tissue. DNA preservation is suitable for genetic studies in samples stored at -80 degrees C for several years. Formalin-fixed, paraffin-embedded tissue was inferior to frozen tissue, but did yield adequate results in many cases depending on the type of fixative solution and time of fixation before embedding. Prolonged fixation in formalin rarely yielded useful DNA. Similar results were obtained in samples from prion diseases. The best results were obtained by using the Qiagen kits (QIAmp DNA Micro) in frozen material, paraffin blocks and formalin-fixed tissue. Genomiphi (TM) and TaKaRa Ex Taq (TM) methods were also assayed in paraffin blocks and in formalin-fixed samples with limited success.