High throughput analysis of buccal scrape reference samples using the Identifiler system on the Applied Biosystems 3500xl Genetic Analyser is described.
This platform is much more sensitive than previous platforms, e.g. 3130xl. The range of signal detection is also much greater and this means that the system is more tolerant to a wide range of input template concentrations. DNA quantity is not a limiting factor in the analysis of buccal scrapes, hence the entire analytical procedure (process) was designed around a target input of 1.5ng, to minimize low level DNA profiles and associated events of allele dropout. A universal stochastic threshold/limit of detection (LOD) of 300 relative fluorescent units (rfu) was applied across all loci. This level is twice that of comparable systems such as SGM Plus analyzed on 3130xl instruments. After analysis of dropout probabilities, heterozygous balance, drop-in and stutter characteristics, rule-sets were programmed into the FSS i-cubed software. The process has a success rate greater than 95 percent. No discordances or mis-designations occurred when applied to a validation set of more than 1,000 samples. (Published Abstract)