UNTCHI Forensic Unit

The UNTCHI Forensic Unit provides screening and DNA testing services of biological evidence related to criminal investigations.

The laboratory currently receives federal funding through the National Institute of Justice to process cases within the state of Texas. These funds allow UNTCHI to provide standard DNA testing services (i.e., autosomal and Y chromosome STR typing and mitochondrial DNA sequencing) to law enforcement agencies within select North Texas counties at no charge. In addition to standard casework analyses and comparisons, specialty testing services such as forensic paternity and kinship analyses are provided to law enforcement agencies statewide.

Testing Services:

Serology Testing: Identification of Biological Fluids

Human Blood

Human Semen

DNA Testing: Identification of Biological Evidence

Nuclear DNA

Autosomal STR Analysis

Y Chromosome STR Analysis

Mitochondrial DNA

Hypervariable Regions 1 and 2 Sequence Analysis

Types of cases accepted for testing:

Homicide

Sexual Assault

Sexual Assault: Criminal Paternity

Robbery

Property Crimes

Types of samples accepted for biological screening:

Sexual assault kits

Possible semen stains

Possible blood stains

Types of samples accepted for DNA analysis:

Biological stains (e.g. blood, semen or saliva) of unknown origin

Sexual assault kits

Fetal material/products of conception

Epithelial contact samples (accepted on a limited basis)

Probative hair samples

The laboratory works with the investigating agency to determine which samples are most suitable for testing. Selection criteria focus on the items of most probative value to the case and the items that are most likely to yield the highest quality, interpretable DNA profiles. The most probative evidentiary items (e.g., items that could potentially link an assailant to a crime scene; items that could potentially link a victim to a suspect or property of the suspect) are prioritized for analysis. Then the types of evidence that are more likely to yield higher quality interpretable DNA profiles are selected, e.g., biological fluids (i.e., blood, semen, saliva) are prioritized over epithelial contact or touch evidence. The number and selection of samples to be tested are determined on a case-by-case and are based on the needs of the investigating agency and the selection criteria previously mentioned. The laboratory typically limits the number of samples processed for each case. Limits on the number of samples processed are intended to be more selective for maximizing information and extend laboratory funding and resources to as many cases as possible. Processing of epithelial contact samples (samples with possible skin cells) is limited and determined on a case-by-case basis. In general, only weapons used to commit the crime and potential personal belongings of the assailant that were recovered from the crime scene will be considered. Due to limited storage and screening space, bulk items such as sheets, comforters, bedding and other extremely large items are not accepted by the laboratory. Cuttings or swabs of suspected stains or biological fluids from these items may be submitted. For those agencies with qualified crime scene personnel, prior screening (serology testing) or sample collection (cutting, swabbing, scraping of material to be tested) from items of evidence can facilitate case processing and reduce turn-around time. Processing of human hair samples for mitochondrial DNA analysis is limited and determined on a case-by-case basis. Due to the ubiquitous nature of hair and the expense and labor and resource demand of mitochondrial DNA testing, the probative value and significance of an evidentiary hair must be well established for testing approval. The hair must be examined by a qualified hair examiner to determine: the hair is of human origin; the hair is foreign to the known victim standard or other applicable known standards; and the presence/absence of cellular root material. This report must accompany the hair submission.

Evidence Submission Form:

The completed Forensic Casework Evidence Submission Form must accompany each case submission. Please fill out the form fully and completely.

Possible blood stains

A brief case synopsis that explains the nature of the crime and details the origin of the evidence submitted and its relation to the offense is strongly encouraged.

UNTCHI reports will be issued to the email addresses provided by the investigating agency on page one of the evidence submission form.

The Chain of Custody section must be signed and dated to indicate the release of the evidence to the laboratory for testing.

Supporting Documentation for Case Submission:

Applicable supporting documentation should be provided with each case submission. The documents provided should record the nature of the offense, number of assailants, and origin of the evidence. A police offense report will suffice for most submissions. Additional documentation is needed for sexual assault kits, items with prior serology testing and hair evidence.

Required Documentation:

1. A police offense report for all case submissions.

2. A sexual assault nurse examination or hospital report for each sexual assault kit submission.

3. Serology reports for any items submitted with prior serology testing conducted by another laboratory.

4. Hair/Trace reports for all hair evidence submissions.

Case Submission:

Cases can be submitted in person by appointment or shipped through an overnight trackable courier. For submission appointments or shipping instructions, please call the property room at 1-800-763-3147.

UNT Center for Human Identification
Attn: Forensic Unit
3500 Camp Bowie Blvd
Fort Worth, TX 76107

Test Results / Reports:

UNTCHI issues a report documenting the results and conclusions of all tests performed. Reports are issued via electronic mail to the investigating agency email addresses provided on the evidence submission form.

UNTCHI analysts are available to discuss results and interpretation of the DNA evidence with the investigating agency. An analyst contact number is provided on the last page of all UNTCHI reports. Only with permission from the investigating agency, the results may be discussed with additional agencies or persons such as prosecutors or defense attorneys.

Combined DNA Index System (CODIS):

UNTCHI enters all eligible DNA profiles into the Combined DNA Index System (CODIS). Profiles meeting the required criteria are uploaded to the state and national levels of CODIS

CODIS hit notifications are sent to the investigating agency contact provided on the evidence submission form.

Upon notification of a convicted offender hit, the investigating agency should collect a reference sample from the identified suspect and submit it to UNTCHI for testing. Once testing of the reference sample is complete, a new report will be issued by UNTCHI detailing the conclusions of the suspect comparison to the original evidence processed.