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AGTC has traditionally used a combination of conventional protein loci and RFLP DNA loci detected colorimetrically for paternity testing. Though the RFLP loci are highly polymorphic and of great utility in resolving cases of disputed paternity, the requirement of 1 – 5mg of DNA for colorimetric detection make the technology less useful when buccal swabs or blood cards are used. Multiplex STR typing systems (CTT and FFV, Promega Corporation, Madison, WI) with silver stain detection were implemented to solve some of the problems of non-isotopic RFLP technology. However, silver staining produced its own problems. The availability of inexpensive fluoroimaging through the use of Genomyx SCÔ fluorescent scanner (Genomyx Corp., Foster City, CA) allowed the introduction of fluorescent multiplex STR loci (CTTv, FFFL, PowerPlexÔ, Promega Corporation, Madison, WI) to parentage determination. Paternity cases are currently screened with a battery of five conventional IEF systems and the CTTV STR multiplex (GenePrintÔ, Promega Corporation, Madison, WI). Using this system, approximately 75% of cases were completed to AGTC’s level of scientific certainty (power of exclusion >99%, combined paternity index >100). The remaining 25% of cases were completed by testing with an additional fluorescent STR multiplex (FFFL, GenePrintÔ, Promega Corporation, Madison, WI). As the Genomyx SCÔ fluorescent scanner can read both fluoroscein and tetramethyl rhodamine it will be possible to add the PowerPlexÔ when it is routinely available. Fluorescent imaging reduced the labor costs of PCR based testing by approximately 40% by elimination of the labor intensive silver staining. Fluorescent STR multiplexes also provided a suitable replacement for the RFLP testing. Changing to an STR-PCR based combination system from an RFLP based combination system, reduced the turn-around time from approximately 20 calendar days to 15 calendar days or approximately a 25% decrease in turn-around time, with a single DNA analyst handling casework formerly performed by two DNA analysts.