Nuclear-DNA Unit

DNA—Nuclear

Mission

The Nuclear DNA Unit (NDNAU) provides forensic biological services to the FBI and other duly constituted law enforcement agencies to support the investigative and intelligence priorities through evidence testing using forensic serological and Nuclear DNA methodologies.

The Team

Forensic examiners, a biologist, and a DNA program analyst

The Work

In 1998, the FBI Laboratory began using DNA testing in forensic cases. Prior to 1998, serological testing was used in detecting, characterizing, and attributing bodily fluid strains found on evidence submitted to the laboratory. The first DNA tests were used primarily in the same fashion and with the same purpose as the serological test. The major advantage of DNA testing was the yielding of genetic profiles that were generally more discriminating (possessed by fewer people) than serology markers. The FBI continues to use serological tests to detect and characterize bodily fluid stains on submitted evidence. In addition to the use of serological testing, the FBI uses Polymerase Chain Reaction (PCR) and Short Tandem Repeat (STR) analysis to detect minute amounts of biological material to generate DNA profiles sufficiently rare to be associated to a single individual to a reasonable degree of scientific certainty.  

Currently, the NDNAU performs serological testing to detect blood and semen during Nuclear DNA testing in biological stains and or on evidence items from which DNA can be recovered depending upon the usage.

At this time, the NDNAU accepts and examines cases from FBI field offices; other federal agencies such as Bureau of Indian Affairs, DEA, and Coast Guard; United States Attorney offices; military tribunals; and other international law enforcement agencies through FBI legat offices in matters involving United States citizens. NDNAU also accepts cases from state, county, and municipal law enforcement agencies in the United States and its territories if the submitting agency does not have access to its own crime laboratory. We prioritize our cases in accordance with the FBI Director’s priorities of counterterrorism, cyber-based/ high technology crimes, public corruption, civil rights, transitional/national criminal organizations/ enterprises, major white-collar crime, significant violent crime, and support of federal, state, local, and international agencies.

The NDNAU participates in the Combined DNA Index System (CODIS) and electronically exchanges and compares DNA profiles with other federal, state, and local crime laboratories. In fact, the unit is statutorily responsible for evaluating the suitability of all of its evidence profiles for uploading into the Forensic Index of CODIS so that these profiles can be compared to evidence profiles from other laboratories as well as to profiles contained in the Convicted Offender Index of CODIS. The Nuclear DNA Unit also performs testing for the National Missing Person DNA Database (NMPDD) of CODIS to assist in the identification of missing persons and unidentified human remains. These DNA profiles are placed into one of the three different indices within the National DNA Index System (NDIS): the Missing Person Index, the Biological Relatives of Missing Persons Index, or the Unidentified Human Remains Index.

If you have any questions about serological and/or DNA testing, please contact us at (703) 632-8446. If you have questions regarding submission of evidence to the FBI Laboratory, please contact the Laboratory’s Evidence Control Unit (ECU) at (703) 632-8360.