DNA Evidence – How Identifying Evidence with DNA Analysis ?


Recognizing DNA Evidence

Since only a few cells are needed for a useful DNA sample, the list below identifies some areas at the crime scene or on the victim that may contain valuable DNA evidence.

The following list shows Possible Locations or common sources of DNA evidence:

  • A blanket, pillow, sheet which could contain sweat, hair, urine, saliva or semen
  • A weapon, such as a baseball bat, fireplace poker or knife, which could contain sweat, skin, blood or other tissue
  • A toothpick, cigarette butt, bottle, can or postage stamp, all of which could contain saliva
  • A used condom, which could contain semen or vaginal or rectal cells
  • Bed linens, which could contain sweat, hair, blood or semen
  • A fingernail or partial fingernail, which could contain scraped-off skin cells
  • A hat, bandanna, or mask, which could contain sweat, hair or dandruff
  • A facial tissue or cotton swab, which could contain mucus, sweat, blood, semen or earwax

Remember, even though a stain cannot be seen, there may be enough cells for DNA typing. Furthermore, DNA does more than just identify the source of the sample; it can place a known individual at a crime scene, in a home, or in a room where the suspect claimed not to have been. The more victim service providers know about properly identifying, collecting, and preserving DNA evidence, the more powerful a tool it becomes.

These are chain-of-custody techniques, which guarantee the lawful integrity of the examples as they move from collection to investigation.

 DNA collection and Analysis

DNA collection and Forensic DNA Analysis give the criminal justice field a powerful tool for convicting the guilty and exonerating the innocent. These pages provide general information on a wide range of topics.

Only one-tenth of a single percent of DNA (about 3 million bases) differs from one person to the next. After extracting DNA from bone, hair, blood or other body tissue or product, scientists record an individual’s variations at these bases to generate their ‘DNA profile.’
In criminal cases, this generally involves obtaining samples from crime-scene evidence and a suspect, extracting the DNA, and analyzing it to characterize the variations at a set of specific variable regions (markers).

If the sample profiles don’t match, the person did not contribute the DNA at the crime scene.
If the patterns match, the suspect may have contributed the evidence sample. DNA from crime scenes also can be compared to profiles stored in a database.

Types of Samples Suitable for DNA Testing

  • Tests From Unidentified Bodies: Tests gathered from unidentified bodies can incorporate blood, buccal swabs, hairs, bone, teeth, fingernails, tissues from inner organs (counting the mind), muscle, and skin.
  • Reference Samples From Known Individuals: The most well-known reference tests gathered from realized people are blood, oral/buccal swabs, or potentially culled hairs (e.g., head, pubic).

Please call The Carlson Company to walk you through Possible Locations of DNA Evidence and sources of DNA. Get 100% confidential DNA Analysis report, accurate infidelity DNA test results from the certified lab.

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