Low Cost DNA Molecular Weight Marker: Primer-Directed Synthesis from pGEM-T Easy Vector

A low cost DNA molecular weight marker was produced by a marker primer-directed synthetic method using pGEM-T Easy vector as the DNA template. Seven primers were used to amplify eight different DNA fragments, which were 150, 300, 375, 500, 700, 1,000, 1,200 and 1,625 bp, from bacterial culture containing pGEM-T Easy vector. Polymerase chain reactions (PCR) for all marker loci required the same optimal annealing temperature, which allowed all the PCR to be completed in a single run. To obtain the molecular weight marker, the PCR product of each locus was mixed together and directly used as marker without any further purification. This custom made molecular weight marker was found to be approximately 17 to 49 times less expensive than other commercial 100 bp DNA ladder markers. Graphical abstract