Water itself doesn't inherently remove DNA, but it significantly impacts its stability and recovery. The effect depends on several factors, including the type of water, the duration of exposure, and the environment.
How Water Affects DNA
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DNA Degradation: Studies show that exposure to various types of water (freshwater, swamp water, saltwater) leads to substantial DNA degradation over time. A study on human bone samples found significant DNA loss in aqueous environments over a 72-hour period. Effects of Different Types of Water on the Degradation Rate of Human ... This degradation is due to enzymatic activity and chemical processes in the water that break down the DNA molecule.
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DNA Solubility: While DNA isn't directly dissolved by water, the water can affect the physical state and availability of DNA for extraction and analysis. For instance, DNA bound to a substrate (like clothing) might be more easily washed away with water, reducing the amount recoverable. However, DNA can persist on clothing even after prolonged water exposure. Persistence of DNA on clothes after exposure to water for different ...
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Contamination: Water sources themselves contain a significant amount of microbial DNA. Consequently, extracting DNA from water samples might yield a mixture of DNA from different sources, including environmental DNA and any target DNA originally present.
Practical Implications
- Forensic Science: Water significantly impacts the preservation of DNA evidence at crime scenes. Submerged objects may lose significant DNA due to degradation or washing away.
- Environmental Monitoring: Water samples used for environmental DNA (eDNA) studies require careful handling to prevent DNA degradation and contamination.
- DNA Extraction: Water's impact on DNA requires careful consideration during the extraction process. Specific protocols exist for extracting DNA from aqueous environments, accounting for potential contamination and degradation. How do you extract total DNA from water samples?
While water might facilitate the removal of some DNA from surfaces, it doesn't actively remove all DNA. The remaining DNA may still be degraded or difficult to extract, depending on the circumstances.
