Hi, I have done an RT-PCR experiment from which i have calculated fold changes when comparing the expression of several genes in healthy vs disease. In a second independent experiment i have done the same so that i get again a list of fold changes healthy vs diseaseA (fold changes exp1) healthy vs diseaseA (fold changes exp2) geneA 2 1.5 geneB 1.5 1.4 geneC 2.5 2.8 geneD 5 1.5 geneE 1.8 1.9 geneF 1.5 1.4 geneG 1.4 1.3 ..... For geneD I have 5 fold changes in one experiment and 1.5 fold changes in another expermient. Is there any stasticial method to see if the difference between the two fold changes is significant for geneD ? any pvalue ? thanks