Biomedical Engineering: Bridging Medicine and Technology 1st Edition by Veronique Tran,Mark Saltzman

Exercise 15

To be able to properly analyze a sample of DNA, you need to have at least 1 µg of the DNA of interest. Assumptions: PCR is run with 30 cycles; molecular weight per nucleotide in DNA is about 660 g/bp (330 g/bp for single-stranded DNA or RNA); bp = base pair.
a. Given that you can use PCR to amplify DNA from the original sample and the size of the fragment to be amplified is 10,000 nucleotides long, estimate how many DNA molecules you need to obtain the minimum amount required to analyze the sample.
b. Suggest a way to increase your sensitivity. In other words, amplify the DNA starting from even fewer molecules of template DNA.