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RT control product appears only 5 cycles away from unknown samples - (Sep/18/2006 )

Hi!! I hope someone can help me! I was wondering why my -rt negative controls are showing a product only 5 cycles later than the unknown samples!? It should not be contamination because I have repeated this successfully three times. Can I simply add more template for my unknown samples (cDNA's) to make the difference in cycles become greater, as long as I add the same amount of template to all pcr reactions, I thought it should be valid, or??

Thank you so much for your help...suggestions are welcome!



I'm sorry but in a negative control you shouldn't have any product. Are you sure that your reagents are not contaminated? If they are, you can repeat this thousands of times...


it could be that you have successfully gotten approximately the same amount of gDNA contamination three times; I would not rule out contamination