HIGH-RESOLUTION CAPILLARY ELECTROPHORESIS OF FORENSIC DNA USING A NON-GEL SIEVING BUFFER

For the routine application of capillary electrophoresis to forensic DNA analysis, a number of requirements must be met. In the analysis of DNA amplified by the polymerase chain reaction, these requirements include high resolution and consistent and reproducible runs. Genetic markers of interest in this study consist of DNA fragments 200 or more base pairs long with repeat units as small as 2 base pairs. Normally gel-filled columns are necessary to resolve such small differences in size, however these columns suffer from a limited lifetime and a buildup of impurities over time. This paper reports an alternative method using a non-gel sieving buffer prepared from hydroxyethyl cellulose. Application of this method illustrates that a refillable, coated, open tubular column can achieve the necessary separation efficiency. Examples are given showing application of the technique to a number of genetic markers of interest in forensic DNA analysis.