Are there components in biological samples that can inhibit the REPLI-g reaction?

Some components present in biological samples may inhibit the REPLI-g reaction. For example, if too much blood is added, excess heme present will have an inhibitory effect. For this reason, we limit the volume of blood lysates to use in the WGA reaction. Buccal swab samples and mouthwash specimens should be processed taking care to pellet and wash the cells, as this will produce cleaner lysates and better amplification product.