Figure 1. Evaluation of the subtraction efficiency by PCR using the housekeeping gene actin and the melanocyte marker EDNRB. A: Reduction of actin expression in the TP31 subtracted library compared to unsubtracted TP31 cDNA. B: Reduction of actin expression in the UVM subtracted library compared to unsubtracted UVM cDNA. C: Enrichment of EDNRB expression in the UVM subtracted library compared to unsubtracted UVM cDNA. Samples were taken after 18, 23, 28, and 33 PCR cycles.