Transfection was used to introduce siRNA into human fibroblasts. In the attempt to knockdown SCF gene expression, it was necessary to validate how successful its genetic knockdown was. Comparisons between the controlled, regular fibroblast cells, and the same fibroblast cells with introduced 25 nM siRNA delineated the productive knockdown in the mRNA expression levels. Figure 1 shows the qPCR-validated knockdown efficiency of SCF mRNA levels. qPCR is a quantification technique used to determine the mRNA expression levels of, in this case, the amplified SCF gene. Transfection of Hs68 human fibroblasts with 25 nM SCF siRNA showed a significant decrease in SCF gene expression 48 h after the transfection compared with regular Hs68 fibroblasts. Using the transfection method and the qPCR confirmation, the results indicated that a successful >75% of SCF mRNA expression levels were effectively silenced in Hs68 cells.