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. 2025 Jul 15;15(1):25637.
doi: 10.1038/s41598-025-08257-y.

Feasibility of extracting usable DNA from blood samples stored up to 21 years in the DiPiS study

Agnes Andersson Svärd  1 , Ellen Viberg  2 , India von Platen  2 , Ida Jönsson  2 , Markus Lundgren  3   4 ; DiPiS study group
Collaborators, Affiliations

Feasibility of extracting usable DNA from blood samples stored up to 21 years in the DiPiS study

Agnes Andersson Svärd et al. Sci Rep. .

Abstract

This study assesses the feasibility of extracting high-quality DNA from blood samples stored at - 20 °C for up to 21 years under suboptimal conditions. It addresses sample mishandling in research, where many samples lack proper biobank protocols. Prior studies focused on short-term storage and controlled conditions, highlighting the negative effects of freeze-thaw cycles. This study evaluates whether DNA from long-term stored samples under suboptimal conditions can still meet quality standards for research purposes. Genomic DNA was extracted from 1012 capillary blood samples from the Diabetes Prediction in Skåne study. Samples were stored at - 20 °C for 7-21 years, and DNA was isolated using QIAamp DNA Blood Mini kits. DNA quantity, purity, and quality were analysed using spectrophotometry and automated electrophoresis. Overall, 75.7% of samples met quality standards for DNA quantity (≥ 20 ng/µL) and purity (A260/280 ratio 1.7-1.9), with the highest proportion in 12-year samples (83.5%). DNA quality was further assessed in 270 samples, where 57.8% had a DNA Integrity Number (DIN) of 7 or higher. This study suggests that historical blood samples stored under suboptmal conditions can still be viable for modern genomic analyses.

Keywords: Blood sample; DNA concentration; DNA isolation; DNA quality; Long-term sample storage.

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Conflict of interest statement

Declarations. Competing interests: The authors declare no competing interests. Ethical approval: The samples analysed in this study were collected as part of the DiPiS study at Lund University. The DiPiS study was approved by the Regional Ethical Review Board in Lund (Dnr 2009/244, Dnr 2014/196, Dnr 2015/861and Dnr 2019-03,222) and complied with institutional and national research ethics standards including the 1964 Helsinki declaration and its later amendments or comparable ethical standards. In the DiPiS study, initiated in 200041,42, application of a eutectic mixture of lidocaine cream preceded blood draws to reduce pain. Informed consent was obtained from the parents of the research subjects to participate in the present cross-sectional follow-up investigation

Figures

Fig. 1
Fig. 1
DNA concentration (ng/μL) (a) and A260/280 ratio (b) of 1012 DNA samples in the DiPiS study stratified by the years they were obtained. The colours (red, green, blue) corresponds to a low ratio (< 1.7), ratio within satisfactory range (1.7–1.9) and high ratio (> 1.9), respectively. In (b), an outlier with ratio 2.4 has been removed from the sample age of 7 years. Kruskal–Wallis test (pglobal = 1.2e-06) suggest a significant difference between the groups. Pair-wise comparison of ratio, with samples stored for 7 years as reference showed a significant difference with samples stored for 21 (padj = 0.001), 16 (padj = 5.32e-06) and 12 (padj = 0.043) years, respectively. Concentrations and A260/280 ratios were measured by NanoQuant Plate in a Tecan Infinite 200 Pro reader.
Fig. 2
Fig. 2
DNA yield (µg) per 1 mL of blood cell sample. Range and distribution of DNA yields per 1 mL of blood cells isolated from frozen blood cell samples stored over 7–21 years at -20 °C during which they have been heavily mistreated. In pair-wise comparisons with the samples stored for 7 years as reference, a statistically significant difference in yield was observed in samples stored for 12 and 16 years. DNA yields were calculated from concentrations measured by NanoQuant Plate in a Tecan Infinite 200 Pro reader.
Fig. 3
Fig. 3
DNA integrity number (DIN) measured in base pairs (bp), stratified by storage duration and colored by fragment size. Outliers with a DIN value below 5.1 have been removed. Kruskal–Wallis test (pglobal = 0.032) suggest a significant difference between the groups. Pair-wise comparison with samples stored for 7 years as reference showed significant difference with samples stored for 21 years (padj = 0.031). DIN’s and fragment sizes were measured by Agilent 2200 TapeStation.
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References

    1. Miller, S. A., Dykes, D. D. & Polesky, H. F. A simple salting out procedure for extracting DNA from human nucleated cells. Nucleic Acids Res.16, 1215. 10.1093/nar/16.3.1215 (1988). - PMC - PubMed
    1. Griffiths, L. & Chacon-Cortes, D. Methods for extracting genomic DNA from whole blood samples: current perspectives. J. Biorepos. Sci. Appl. Med.10.2147/bsam.s46573 (2014).
    1. Holland, N. T., Smith, M. T., Eskenazi, B. & Bastaki, M. Biological sample collection and processing for molecular epidemiological studies. Mutat. Res.543, 217–234. 10.1016/s1383-5742(02)00090-x (2003). - PubMed
    1. Cushwa, W. T. & Medrano, J. F. Effects of blood storage time and temperature on DNA yield and quality. Biotechniques14, 204–207 (1993). - PubMed
    1. Dagur, P. K. & McCoy, J. P. Jr. Collection, storage, and preparation of human blood cells. Curr. Protoc. Cytom.73, 5.1.1-5.1.16. 10.1002/0471142956.cy0501s73 (2015). - PMC - PubMed

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