CODIS
Definition
The FBI's Combined DNA Index System, the US national STR-based forensic DNA database. Contains profiles from convicted offenders, arrestees, and unidentified crime-scene samples. Not accessible through IGG workflows because STR profiles are not compatible with consumer SNP array formats.
- Launch standard
- 13 STR loci
- Current standard (since 2017)
- 20 STR loci
- Database scope
- Offenders, arrestees, unidentified crime-scene samples
Common questions
What is CODIS and why does it matter in forensic DNA work?+
CODIS is the Combined DNA Index System, the FBI's national database of DNA profiles from offenders, arrestees, and crime-scene samples. It became the global standard reference for forensic DNA matching because it defined which genetic markers, called STR loci, labs should test for consistent, searchable results across jurisdictions.
How many genetic markers does CODIS use?+
CODIS originally specified 13 core STR loci for typing. In January 2017, this was expanded to 20 loci. These markers are now the universal reference set that forensic labs follow when creating DNA profiles.
How many DNA profiles does the CODIS database hold?+
The NDIS (National DNA Index System), which holds profiles typed at CODIS loci, contains tens of millions of offender and arrestee profiles. This large database makes it a powerful tool for matching crime-scene DNA to known individuals.
Related terms
- STR (Short Tandem Repeat)
- A genomic locus where a 2, 7 base-pair unit is repeated in tandem a variable number of times between individuals. The variation...
- Amelogenin
- A gene on both the X and Y chromosomes used for sex determination in forensic STR kits. The X-allele amplicon is approximately...
- Autosomal vs Mitochondrial DNA
- Autosomal DNA is nuclear, biparentally inherited, present as two copies per cell. Mitochondrial DNA is cytoplasmic, maternally inherited, present in hundreds to...
- Barbara Rae-Venter
- The genetic genealogist who led the family-tree reconstruction in the Golden State Killer investigation. Previously used the same technique to identify an...
- Bharatiya Sakshya Adhiniyam 2023 (BSA)
- India's current evidence statute, which replaced the Indian Evidence Act 1872. Section 63 of the BSA governs electronic records and requires a...
- Capillary Electrophoresis
- Size separation of fluorescently labelled PCR products through a polymer-filled capillary on an instrument like the ABI 3500. Output is an electropherogram.
- Centimorgans (cM)
- The unit of genetic map distance used to measure shared DNA between individuals. A first-degree relative shares approximately 2,550 cM; a third...
- Chromosome
- A discrete, condensed structure consisting of a single long DNA molecule complexed with histone proteins. Humans normally carry 46 chromosomes in 23...
- Cold Hit
- A database match between a crime-scene DNA profile and an offender or arrestee profile where no other investigative lead identified the suspect....
- ESS (European Standard Set)
- The set of STR loci required for profiles entered into EU national databases participating in Prüm cross-border DNA exchange. Currently aligned with...
- Familial Searching
- The deliberate use of partial DNA profile matches in a forensic database to identify biological relatives of an unknown contributor, on the...
- ForenSeq Kintelligence
- A Verogen (formerly Illumina) forensic SNP genotyping kit targeting approximately 10,000 kinship-informative SNPs, designed to generate profiles compatible with consumer genealogy databases...
Explained in these topics
- DNA Evidence: Legislation, Databases and PrivacyCombined DNA Index System: the United States national forensic DNA database, operated by the FBI. It stores STR profiles at local, state, and national levels a...
- DNA in Forensic Science: Structure, Genetic Markers, Extraction and ProfilingCombined DNA Index System. The FBI database that defined the original 13 core STR loci (expanded to 20 in 2017). The standard reference set globally.
- DTC Genealogy: The Golden State Killer Paradigm and GEDmatch PolicyThe FBI's Combined DNA Index System, the US national STR-based forensic DNA database. Contains profiles from convicted offenders, arrestees, and unidentified c...
- Polymorphism, Heredity and the Markers that Identify a PersonCombined DNA Index System, the US FBI's national DNA database software and the set of STR loci it indexes. Expanded from 13 to 20 core loci in January 2017. Th...