I work on serum samples and I'm in a big delimma regarding which primers to choose since I don't have a gene of interest because my purpose is to screen and identify a specific gene.
Hi! Do you mean to say that you want to do an exploratory study to identify candidate biomarkers from serum? If yes, simple PCR will not be able to identify new genes of interest. You must do some high throughput experiments like RNA profiling or exome sequencing or similar experiments with patient samples and control samples and compare the two in order to identify abnormalities in genetic sequence or gene expression in the disease condition.