Presentation Type

Poster Presentation

Abstract/Artist Statement

DNA can be a vital piece of evidence in a court of law; therefore, the integrity of the DNA is essential. If cross-contamination occurs during storage, then the integrity of the evidence becomes jeopardized. Not only does cross-contamination render the genetic evidence problematic, but if left undetected, it has the potential to link an individual to a case they were not previously associated with or compromise DNA what is associated with a case so that it is unusable. Either scenario is not ideal, and every step should be taken to avoid such a situation. The goal of this project is to test DNA storage methods and environments to determine the best way to avoid potential cross-contamination. Known protocols for storing different types of genetic evidence samples are evaluated. When packaged genetic evidence samples are stored in close proximity to one another, there is a higher chance for cross-contamination.

Studies have been conducted on cross-contamination throughout the investigation process. However, no published studies have examined the potential for contamination during the storage process. This study tested two DNA collection methods for the potential of cross-contamination during storage. Three different dry times of buccal swabs and Whatman cards were tested: none, one hour and 24 hours, in triplicate, and then placed into storage with an uncontaminated sample for one of the following times: 72 hours, 14 days, or 45 days. Cross-contamination was detected in the 72 hours and 45 days blank samples. There was no detection of cross-contamination in any of the blank 14 days samples. The statistics revealed there is a statistical significance for the storage time but not dry time. The fisher exact test yielded a 0.00 p-value (α = 0.05) for the Whatman card, while the buccal swabs yielded a 0.054 p-value (α = 0.05). Cross-contamination was detected upon removal from storage demonstrating that further research is needed to better understand cross-contamination during storage.

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Feb 28th, 5:00 PM Feb 28th, 6:00 PM

DNA integrity in forensic samples

UC North Ballroom

DNA can be a vital piece of evidence in a court of law; therefore, the integrity of the DNA is essential. If cross-contamination occurs during storage, then the integrity of the evidence becomes jeopardized. Not only does cross-contamination render the genetic evidence problematic, but if left undetected, it has the potential to link an individual to a case they were not previously associated with or compromise DNA what is associated with a case so that it is unusable. Either scenario is not ideal, and every step should be taken to avoid such a situation. The goal of this project is to test DNA storage methods and environments to determine the best way to avoid potential cross-contamination. Known protocols for storing different types of genetic evidence samples are evaluated. When packaged genetic evidence samples are stored in close proximity to one another, there is a higher chance for cross-contamination.

Studies have been conducted on cross-contamination throughout the investigation process. However, no published studies have examined the potential for contamination during the storage process. This study tested two DNA collection methods for the potential of cross-contamination during storage. Three different dry times of buccal swabs and Whatman cards were tested: none, one hour and 24 hours, in triplicate, and then placed into storage with an uncontaminated sample for one of the following times: 72 hours, 14 days, or 45 days. Cross-contamination was detected in the 72 hours and 45 days blank samples. There was no detection of cross-contamination in any of the blank 14 days samples. The statistics revealed there is a statistical significance for the storage time but not dry time. The fisher exact test yielded a 0.00 p-value (α = 0.05) for the Whatman card, while the buccal swabs yielded a 0.054 p-value (α = 0.05). Cross-contamination was detected upon removal from storage demonstrating that further research is needed to better understand cross-contamination during storage.