Federal Bureau of Investigation DNA Analysis Units

• DATE: Formed in 1998

IDENTIFICATION: Special units of the FBI Laboratory formed to provide DNA testing and related services to all federal, state, and local law enforcement agencies, military tribunals, and US attorneys in the United States and abroad.

SIGNIFICANCE: By providing comprehensive forensic examinations, scientific research, technological advancements, training, expert witness testimony, and maintenance and creation of national DNA database programs, the FBI’s DNA Analysis Units have contributed to the effectiveness of the use of DNA evidence in criminal investigations and in the identification of missing and unidentified persons.

The Federal Bureau of Investigation (FBI) operates one of the world’s largest forensic laboratories. The FBI Laboratory, commonly referred to as the FBI crime lab, comprises branches and sections that are further divided into special units. In 1988, the DNA Unit was established as part of the lab’s Scientific Analysis Section. The new unit included biologists, forensic examiners, specialists in DNA (deoxyribonucleic acid) analysis, and management and program analysts. In 1998, the DNA Unit was divided into two more specialized units: the DNA Analysis Unit I (DNAAU-1) and the DNA Analysis Unit II (DNAAU-2). The Federal DNA Database Unit (FDDU) was established in 2000 as the Federal Convicted Offender (FCO) program under the  DNA Analysis Backlog Elimination Act of 2000.

DNAAU-1 examines evidence from a variety of crimes and provides serological and nuclear DNA testing services. Serological techniques assist in DNA analysis by identifying whether biological stains are blood, semen, or other body fluids. Automation and robotic extraction platforms are used to isolate DNA from the evidentiary samples. DNA samples for testing may be obtained from a variety of other sources, such as saliva left on cigarette butts, envelopes, or beverage bottles, and from sweat deposited inside hats. After extraction, nuclear DNA testing is performed on the evidence, and the findings are compared with the DNA found in reference samples obtained from crime victims or suspects.

The resulting DNA profiles are uploaded into the Combined DNA Index System (CODIS). The National DNA Index System (NDIS), which was created in the late 1990s, serves as the national-level component of CODIS. In 2000, the Federal Convicted Offender (FCO) program was created to collect and manage federal offender DNA profiles within NDIS. FCO became an independent unit in 2009 and was renamed the Federal DNA Database Unit (FDDU). The FDDU processes and uploads approved DNA profiles into NDIS for individuals who are convicted of, arrested for, or facing charges for some federal crimes; individuals who are convicted for certain offenses in the District of Columbia; profiles collected from crime scenes; and non-US citizens who are detained under US authority.

NDIS comparisons of the evidentiary DNA profiles against those in the DNA Index System are performed through CODIS software. If a match is identified, the laboratories that submitted the DNA profiles are notified for further confirmation.

DNAAU-2 analyzes the mitochondrial DNA (mtDNA) sequences in biological evidence from crime scenes, such as hair, teeth, and bones. Nuclear DNA analysis may not be appropriate for such evidential materials, as the DNA may be degraded, so sensitive mtDNA analysis techniques are used. Forensic information attained through these techniques has proven especially useful in cold cases and in cases with only small pieces of biological evidence available.

Unique identification—that is, identification of a specific individual—is not possible using mtDNA analysis, as all maternal relatives inherit the same mtDNA type. DNAAU-2 scientists compare the mtDNA from biological evidence to reference samples of qualifying relatives, such as the mother or siblings, of the person of interest.

The work of DNAAU-2 is also integral to the National Missing Person DNA Database (NMPDD) program. The NMPDD contains available DNA profiles from missing persons, biological relatives of missing persons, and unidentified human remains. Like NDIS, the NMPDD is part of the Combined DNA Index System (CODIS). DNAAU-2 also works in partnership with the Regional Mitochondrial DNA Laboratory Program and maintains the Scientific Working Group on DNA Analysis Methods mtDNA Population Database.

Bibliography

Buckleton, John, et al., editors. Forensic DNA Evidence Interpretation. CRC Press, 2005.

DePalma, Lindsay, et al. “Body Swab DNA Collection in Death Investigations.” FBI Law Enforcement Bulletin, U.S. Department of Justice, 9 Aug. 2024, leb.fbi.gov/articles/featured-articles/body-swab-dna-collection-in-death-investigations. Accessed 10 Feb. 2026.

FBI. “Biometrics and Fingerprints.” Law Enforcement Resources, le.fbi.gov/science-and-lab/biometrics-and-fingerprints/federal-dna-database-unit. Accessed 10 Feb. 2026.

“Frequently Asked Questions on CODIS and NDIS.” FBI, www.fbi.gov/how-we-can-help-you/dna-fingerprint-act-of-2005-expungement-policy/codis-and-ndis-fact-sheet. Accessed 10 Feb. 2026.

Kirby, Lorne T. DNA Fingerprinting: An Introduction. Oxford University Press, 1992.

Rudin, Norah, and Keith Inman. An Introduction to Forensic DNA Analysis. 2nd ed., CRC Press, 2002.