Densitometric DNA Analysis in Agarose Electrophoretic Gels

Agarose gel electrophoresis is a basic separation tool used in molecular biology, mostly for qualitative DNA analysis. There are constraints limiting its use in quantitative analysis, namely low repeatability and a narrow linear range. However, by using an internal standard or internal normalization, repeatability and linear range could be significantly improved. In the work discussed in this paper it was shown that an approximately fivefold improvement in repeatability and an over threefold wider linear range could be achieved by applying internal normalization. Using the proposed approach, genetic markers, for example RAPD and PCR—RFLP, or even microsatellite markers, could be conveniently quantitatively assessed using agarose gel electrophoresis.