Question

Explain what is a PCR inhibitor.

Answer 1

PCR inhibitors are wide range of chemical substances which inhibit polymerase chain reaction, thus resulting in lower degree of amplification or no amplification. These are introduced as impurities from sample DNA (polysaccharide in plant DNA, calcium ions from milk, Hemoglobin in blood sample). PCR inhibitors can directly bind to DNA (DNA binding proteins) or have effect on thermo stable DNA polymerase or it can reduce availability of magnesium ion which is a cofactor for DNA polymerase. PCR inhibitors can be removed by purification of samples.