The Dual Nature of Nucleic Acid Persistence: Enhancing Forensic Accuracy and Encountering Limitations

Bowman Iverson^*
*Correspondence: Bowman Iverson, Department of Biology, University of Potsdam, D-14476 Potsdam, Germany, Email:

Introduction

Nucleic acids, including Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA), have long been considered the cornerstone of modern forensic science. These biomolecules serve as a unique biological signature, offering insights into the identity, lineage, and even the health conditions of individuals. The persistence of nucleic acids in various environments, whether at a crime scene, in a biological sample, or in forensic evidence, plays a significant role in enhancing the accuracy of forensic investigations. However, despite their potential, there exists a complex duality in the persistence of nucleic acids, particularly in terms of their stability, degradation, and susceptibility to environmental factors [1]. While the persistence of nucleic acids enhances the likelihood of solving crimes and identifying individuals, it also introduces certain challenges and limitations that forensic scientists must consider. This article delves into the dual nature of nucleic acid persistence in forensic science. On one hand, it explores how nucleic acid preservation contributes to the reliability and precision of forensic outcomes, while on the other hand, it addresses the limitations and obstacles forensic professionals face when relying on nucleic acid evidence in complex, real-world scenarios [2].

Description

Forensic science relies on a wide range of biological and chemical markers to identify individuals, confirm the presence of substances, and reconstruct events. Among the most critical of these markers is DNA, a molecule that encodes the genetic blueprint of an individual. Due to its uniqueness to each person (except for identical twins), DNA is a powerful tool in criminal investigations, paternity testing, disaster victim identification, and much more. In addition to DNA, RNA can also play a significant role in forensic analysis, especially in identifying biological evidence that may be transient in nature, such as blood or saliva. DNA collected from blood, hair, skin cells, semen, or other bodily fluids can be used to link a suspect to a crime scene or to eliminate innocent individuals from suspicion. DNA is often used to identify deceased individuals, especially in cases where traditional methods of identification (e.g., dental records or fingerprints) are not available or reliable. Advances in DNA testing have played a pivotal role in overturning wrongful convictions, highlighting the importance of accurate and reliable nucleic acid analysis in ensuring justice [3].

The persistence of nucleic acids is one of the key aspects that make them invaluable in forensic science. Nucleic acids, especially DNA, have been found to remain intact under a wide variety of conditions, sometimes for extended periods of time. In ideal conditions, DNA can last for thousands of years, as demonstrated by the successful extraction of ancient DNA from archaeological remains. This remarkable stability is largely attributed to DNA’s chemical structure, as well as its capacity to withstand certain environmental conditions. Cold, dry, and low-oxygen environments are particularly conducive to the preservation of nucleic acids. Examples include soil, bone, teeth, hair, and other biological samples that have been preserved in such environments. Forensic scientists often focus on recovering DNA from these sources in challenging or cold crime scenes where traditional methods of identification might be unreliable. In many instances, forensic scientists are able to retrieve DNA from forensic samples such as blood stains, saliva, semen, and other bodily fluids. Biological materials, especially when preserved in controlled or less disturbed conditions, provide reliable genetic information that can be compared to DNA databases to identify perpetrators or victims [4].

One of the main challenges forensic scientists face is the degradation of nucleic acids, particularly in adverse environmental conditions. Factors such as temperature, humidity, and exposure to light can accelerate the breakdown of DNA, leading to partial or complete degradation of the genetic material. Degraded DNA is often fragmented into smaller pieces, making it more difficult to analyze and interpret. High temperatures and moisture are known to cause hydrolytic and oxidative damage to DNA, resulting in strand breaks, base modifications, and the loss of genetic information. Forensic samples collected from crime scenes exposed to heat, rain, or sunlight are particularly vulnerable to such degradation. Soil, bacteria, fungi, and other environmental contaminants can also influence the persistence of nucleic acids. The presence of microbial communities, such as those found in soil, can rapidly degrade DNA, making it challenging to retrieve reliable samples from such environments. Additionally, soil-based samples often suffer from contamination, as other biological materials, such as plant DNA or animal hair, may also be present. Nucleic acids are also susceptible to degradation due to exposure to certain chemicals, including those found in cleaning agents, acids, and other reactive substances. Crime scenes where chemicals are used (e.g., in arson or manufacturing) pose additional challenges to DNA retrieval [5].

Conclusion

The dual nature of nucleic acid persistence in forensic science reveals both its remarkable potential and its inherent limitations. On the one hand, nucleic acids, particularly DNA, offer a powerful tool for forensic identification, enabling accurate, reliable results even in challenging conditions. However, the persistence of nucleic acids is not without its challenges. Environmental degradation, contamination, and the complexity of DNA mixtures introduce significant hurdles that forensic scientists must overcome. The limited persistence of RNA further complicates the application of nucleic acids in forensic science, particularly in cases requiring precise and long-term analysis. Despite these limitations, advancements in forensic technology and methods continue to improve the reliability of nucleic acid-based analysis. As research progresses, forensic scientists will be better equipped to address the challenges of nucleic acid degradation and contamination, enhancing the overall accuracy of forensic investigations. By understanding both the strengths and weaknesses of nucleic acid persistence, forensic professionals can continue to harness this powerful tool to solve crimes, exonerate the innocent, and ensure justice is served.

Acknowledgment

We thank the anonymous reviewers for their constructive criticisms of the manuscript.

Conflict of Interest

The author declares there is no conflict of interest associated with this manuscript.

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