A comparative evaluation of four DNA extraction protocols from whole blood sample

Area of Science:

• Molecular Biology
• Biotechnology
• Bioinformatics

Background:

• Deoxyribonucleic acid (DNA) is fundamental to all organisms, carrying genetic information.
• DNA extraction from whole blood is a critical technique in molecular biology laboratories.
• Various protocols exist for DNA extraction, each with distinct characteristics.

Purpose of the Study:

• To compare four DNA extraction protocols from blood samples.
• Evaluate protocols based on time, DNA yield, purity, toxicity, and PCR functionality.
• Identify the most efficient and safe DNA extraction method for laboratory use.

Main Methods:

• Modified phenol-chloroform extraction.
• Two salting-out and enzyme-free methods.
• Commercial DNA extraction kit (Roche diagnostics GmbH).
• Analysis using gel electrophoresis and Nanodrop spectrophotometry.
• Polymerase Chain Reaction (PCR) for DNA functionality assessment.

Main Results:

• No significant differences in DNA purity (A260/A280) across methods.
• Phenol-chloroform method yielded the highest DNA quantity (ng DNA/μl).
• Phenol-chloroform method was the most toxic and time-consuming.
• Commercial kit was most expensive but fastest and safest.
• DNA functionality in PCR was comparable across methods.

Conclusions:

• While phenol-chloroform offers high DNA yield, its toxicity and time requirements are drawbacks.
• Commercial kits provide a balance of speed, safety, and acceptable DNA yield and purity.
• The choice of DNA extraction method depends on laboratory priorities regarding cost, time, safety, and yield.