Chen Wenlong Carl, Kerr Robyn, May Andrew, Ndlovu Babongile, Sobalisa Anelisa, Duze Sanelisiwe T, Joseph Lavania, Mathew Christopher G, Babb de Villiers Chantal
1 National Cancer Registry, National Health Laboratory Service , Johannesburg, South Africa .
2 Sydney Brenner Institute for Molecular Bioscience, University of the Witwatersrand , Johannesburg, South Africa .
Biopreserv Biobank. 2018 Apr;16(2):106-113. doi: 10.1089/bio.2017.0050. Epub 2018 Jan 3.
Long-term storage of whole blood can affect the integrity of DNA if it is not done under optimal conditions. The aim of this study was to determine whether long-term storage (2-19 years) of whole blood samples at -30°C had a negative effect on the quality or quantity of genomic DNA that could be recovered at extraction. Genomic DNA was isolated from 2758 whole blood samples collected in 4 mL EDTA vacutainers from 1997 to 2012. DNA was extracted using the Qiagen FlexiGene DNA kit. The average storage duration at -30°C was 12 years. The quality and quantity of the isolated DNA were assessed using spectrophotometry (NanoDrop™), a fluorometric assay for double-stranded DNA (Qubit™), and agarose gel electrophoresis. The mean DNA yield per sample was found to be 114 μg from whole blood volumes that ranged from 0.5 to 4 mL. The mean A260/280 ratio and median A260/280 ratios were both 1.8. No correlation was found between the duration of storage and the total yield or the quality of DNA extracted. These data suggest that high-quality DNA can be extracted from whole blood samples that are stored at -30°C for up to 19 years.
如果全血不是在最佳条件下储存，其长期储存会影响DNA的完整性。本研究的目的是确定全血样本在-30°C下长期储存（2至19年）是否会对提取时可回收的基因组DNA的质量或数量产生负面影响。从1997年至2012年采集于4 mL EDTA真空采血管中的2758份全血样本中分离基因组DNA。使用Qiagen FlexiGene DNA试剂盒提取DNA。在-30°C下的平均储存时间为12年。使用分光光度法（NanoDrop™）、双链DNA荧光定量检测法（Qubit™）和琼脂糖凝胶电泳对分离出的DNA的质量和数量进行评估。发现每个样本的平均DNA产量为114μg，全血体积范围为0.5至4 mL。平均A260/280比值和中位数A260/280比值均为1.8。未发现储存时间与提取的DNA总产量或质量之间存在相关性。这些数据表明，可以从在-30°C下储存长达19年的全血样本中提取高质量的DNA。
