Chain of Custody

For any legal DNA case, the Chain of Custody of the sample is of utmost importance. If the Chain of Custody is disrupted or questionable at any stage of the process, this may jeopardize the acceptance of the results in a legal matter. Therefore Orchid Cellmark has developed strict procedures and systems to ensure that the procedures have been followed.

Chain of Custody involves procedures that apply to the following steps of a DNA test:

1. Identification of the tested party
   
2. Obtaining Consent
   
3. Collection of specimens from the tested party
   
4. Packaging of the specimens
   
5. Shipment of the specimens
   
6. Receipt of the specimens by the DNA laboratory
   
7. Transfer of specimens within the DNA laboratory
   
8. Storage of the specimens

Identification of Tested Party

In order to help ensure that the correct person is tested, the following identification procedure should take place:

• Each client must produce government issued identification (usually photo identification)
  
• An instant photo or photo that is suitable for positive identification must be obtained for each client

This information is recorded on a Client Consent/Chain of Custody form along with information on the date the samples were collected, the name and location of the specimen collector as well as the signature of both the specimen collector and the tested party (or their legal guardian, if under age).

Obtaining Consent

Each adult party tested in a legal test must sign the Orchid Cellmark consent form, consenting to the collection of a cheek swab and to the comparison of DNA from that swab to other parties involved in the DNA test. This form must also be signed by the legal guardian of any child under the age of consent.

Collection of Specimens

All cheek swab specimens must be collected by a third party for a “Court Ready or Legal" test. This ensures that the entire process is unbiased. Orchid Cellmark provides color coded specimen collection kits to our approved specimen collectors. The external packaging and internal swabs are color coded according to the role of the client in the case (mother = pink, child = yellow, alleged father = blue).

The external colored buccal swab kit envelopes are labeled with the client’s name, the date of collection, the specimen collector’s initials and the client’s initials.

The collectors must complete the collection of samples from one client and seal the buccal swab kit for that client before moving on to the next client.

Packaging of Specimens

All buccal swabs are sealed in a buccal swab envelope that is color coded to match the handles of the swabs. Once all the specimen collections for a case are completed, all swab kits pertaining to that case are packaged in a single tamper proof Secure-A-Gene Pak along with the completed Client Consent/Chain of Custody paperwork for that case.

The Secure-A-Gene Pak is sealed by removing an adhesive strip and the specimen collector dates and initials the pak to further protect the package from tampering.

The Secure-A-Gene Pak is then placed into a courier pack.

Shipment of Specimens

All specimens for a Court Ready DNA test are shipped via a national courier such as Federal Express, DHL or UPS. The courier waybill number becomes part of the Chain of Custody record for that case.

Receipt of Specimens

The Accessioning Department of Orchid Cellmark is responsible for receiving and examining each package of DNA specimens that arrive at our laboratory. They inspect the external and internal packages for any signs of tampering. Additionally, they examine the Client Consent/Chain of Custody form to ensure that all information has been provided. The specimens will only be released to the DNA testing laboratory if the package and samples meet all requirements. If so, the samples and Chain of Custody paperwork will be bar-coded and released to the laboratory.

Transfer of Specimens

When the Case Management Department accessions the specimens for DNA testing, each sample is assigned a unique bar code. The DNA laboratory uses this bar code to label paperwork and sampling tubes at each step of the testing process. At every transfer point, the items are scanned against the data in the computer and if the data does not match, the test will not proceed until the issue has been rectified.

Storage of Specimens

The final step in a DNA test, after the release of the report, is the proper storage of the cheek swab and DNA samples. The samples are stored in a secure location within the laboratory by unique barcode number. The cheek swab samples are stored at least 5 years and the isolated DNA samples are stored for at least 30 days, according to accreditation requirements.

Internal Quality Control

Orchid Cellmark has implemented a variety of Quality Control measures to ensure that reagents, equipment and testing methods function as expected and that Chain of Custody is maintained. These processes and procedures are summarized below:

• Use of confirmatory testing to ensure the accuracy of results.
  
• Use of computer verifications to identify matches of specimens regardless of their assignments, i.e., mother, child, or alleged father.
  
• Requirement of a minimum of three exclusions to report exclusionary results, which exceeds the aaBB requirement of two.
  
• Use of the gender/sex marker Amelogenin to assist in confirming the identities of the tested parties by verifying the gender/sex of each party collected.
  
• Raw data is evaluated 3 times to assess accuracy. This procedure exceeds aaBB requirement of 2 independent reviews.
• Utilization of automated processes and equipment whenever possible to eliminate the potential for human error in manipulating the layout and placement of samples during handling and testing.
  
• Use of a proprietary software package containing verification steps to ensure the accuracy of laboratory test results.

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