Why is endpoint PCR an inappropriate and imprecise way to qu

Why is endpoint PCR an inappropriate and imprecise way to quantify the number of copies of template in a starting sample?

Solution

Endpoint PCR has three main stages - DNA amplification, separation of PCR, detection of products

Separation of DNA segments is typically done by agarose gel electrophoresis. The products are then stained with etheiduim bromide and \"detected\" by visualization of bands in gel under UV light. Hence, final results of endpoint PCR can\'t be expressed as numbers. Also results are based on size discrimination, which may not be very precise and is variable from sample to sample. Agarose Gel resolution is very poor (~10 fold.).

Hence, due to Poor Precision, Low sensitivity, Short dynamic range < 2 logs, Low resolution, Size-based discrimination only and inability to express results as numbers endpoint PCR an inappropriate and imprecise way to quantify the number of copies of template in a starting sample