Multivariate Evaluation of DNA Quality Differences in Different Preanalytical Procedures in Mouse Livers

Area of Science:

• Molecular Biology
• Histology
• Genomics

Background:

• Histogenetic research demands high-quality DNA from tissue samples.
• The liver's high enzymatic and transcriptional activity makes its DNA vulnerable to preanalytical mishandling.
• Understanding preanalytical factors affecting liver DNA quality is critical.

Purpose of the Study:

• To assess the impact of various preanalytical procedures on extracted liver DNA quality.
• To identify optimal methods for maximizing DNA yield, purity, and integrity from liver tissues.
• To provide guidelines for reliable liver DNA extraction in research.

Main Methods:

• Evaluated DNA yields, purity, DNA integrity number (DIN), percentage of double-stranded DNA (%dsDNA), and PCR amplification of GAPDH.
• Compared different extraction methods (TissueLyser, mortar and pestle, shear cell disruption).
• Assessed effects of ex vivo ischemia duration, storage time, and temperature (liquid nitrogen vapor vs. -80°C).

Main Results:

• Preanalytical procedures minimally affected DIN and GAPDH PCR efficiency but widely varied DNA yields, purity, and %dsDNA.
• RNase treatment significantly increased %dsDNA.
• TissueLyser method yielded higher DNA purity and %dsDNA compared to manual methods.
• Ex vivo ischemia >30 minutes significantly reduced DNA yields.
• Storage in liquid nitrogen vapor resulted in higher DNA quality than -80°C storage.

Conclusions:

• Preanalytical factors significantly influence liver DNA yield, purity, and %dsDNA, but not DIN or PCR efficiency.
• Optimized protocols include using RNase, TissueLyser for disruption, limiting ex vivo ischemia to 30 minutes, and storing samples in liquid nitrogen vapor.
• These findings are vital for consistent and high-quality liver DNA assessment and management in research.