mystery pcr
 

hy

i extracted genomic DNA from blood in 2 ways:
1- frozen in EDTA tubes by Bioneer extraction kit.
2- fresh in EDTA tubes by Genaid extraction kit .

doing pcr to them:
1- few samples give product, the rest faild...i re extracted failed samples in the same way ,,no result in pcr,,only dimer.

2- in case the fresh blood ,good result.

is there a problem with genomic DNA.