Figure 1. Evaluation of the subtraction efficiency by PCR using the housekeeping gene ACTB and the melanocyte marker EDNRB. A: Depletion of ACTB expression (609 bp) in the subtracted cDNA library compared to unsubtracted UVM cDNA. B: Enrichment of EDNRB expression (231 bp) in the subtracted cDNA library compared to unsubtracted UVM cDNA. Samples were taken after 18, 23, 28, and 33 PCR cycles and separated by electrophoresis.