User Verification - DNA Profiling Albert Edwards

Authentication possessions knowledge characteristics

Biometric systems Automated methods Verification and recognition Living person Physiological and behavioral characteristics

Other Biometric Identifiers DNA

DNA Profiling

DNA profiling principles

Benefits of DNA profiling

PCR

DNA Evidence in Unsolved and Post-conviction Cases. PCR technology makes it possible to obtain conclusive results in cases in which previous testing might have been inconclusive. This can result in the identification of suspects in previously unsolvable cases or the exoneration of those wrongfully convicted. It is important to realize that while testing or retesting may exonerate an individual, exclusionary results may not necessarily prove actual innocence. Prosecutors, defense counsel, the court, and law enforcement should confer on the need for testing on a case-by-case basis.

Creating a DNA profile: The Basics RFLP

PCR use in RFLP

VNTR - Playing the Numbers Game

Using DNA Evidence While the number of repeats at a single VNTR locus can't distinguish an individual from the rest of the population, the combined results from a number of loci produce a pattern unique to that person. Using four loci, the probability that you'd find a given allele combination in the general population is somewhere around 1 in 5,000,000. In the United States, the FBI incorporates 13 sites on average into its profiles. With 26 different bands studied, you'd be incredibly hard pressed to find two unrelated individual with the same DNA profile; the odds of a match in this case are well more than one in a hundred billion. Unless you have a twin, you're statistically two thousand times more likely to win the Publisher's Clearinghouse sweepstakes (1 in 50,000,000) than to have a DNA profile that matches anyone else.

Interpreting DNA Results Inclusion Exclusion Inconclusive

CODIS LDIS SDIS NDIS The FBI Laboratory's Combined DNA Index System (CODIS) blends forensic science and computer technology into a tool for solving violent crimes. CODIS enables federal, state, and local crime labs to exchange and compare DNA profiles electronically, thereby linking crimes to each other and to convicted offenders. CODIS began as a pilot project in 1990 serving 14 state and local laboratories. The DNA Identification Act of 1994 (Public Law 103 322) formalized the FBI's authority to establish a national DNA index for law enforcement purposes. In October 1998, the FBI's National DNA Index System (NDIS) became operational. CODIS is implemented as a distributed database with three hierarchical levels (or tiers) - local, state, and national. NDIS is the highest level in the CODIS hierarchy, and enables the laboratories participating in the CODIS Program to exchange and compare DNA profiles on a national level. All DNA profiles originate at the local level (LDIS), then flow to the state (SDIS) and national levels. SDIS allows laboratories within states to exchange DNA profiles.

CODIS Indexes Forensic Offender CODIS generates investigative leads in crimes where biological evidence is recovered from the crime scene using two indexes: the forensic and offender indexes. The Forensic Index contains DNA profiles from crime scene evidence. The Offender Index contains DNA profiles of individuals convicted of sex offenses (and other violent crimes) with many states now expanding legislation to include other felonies. Matches made among profiles in the Forensic Index can link crime scenes together; possibly identifying serial offenders. Based on a match, police in multiple jurisdictions can coordinate their respective investigations, and share the leads they developed independently. Matches made between the Forensic and Offender indexes provide investigators with the identity of the perpetrator(s). After CODIS identifies a potential match, qualified DNA analysts in the laboratories contact each other to validate or refute the match.

Legal Implications

DNA computers

References References http://www.monkey.org/~aidan/598 http://www.ojp.usdoj.gov/nij/dna_evbro/ http://www.howstuffworks.com/ http://www.fbi.gov/hq/lab/codis/ http://www.interpol.int/Public/Forensic/DNA/ http://www.howstuffworks.com/dna-computer2.htm