Why is MgCI2 used in the PCR?

MgCl2 is used in PCR for several reasons. MgCl2 plays a crucial role in PCR master mixes by enhancing the activity of Taq DNA polymerase. By functioning as a cofactor, MgCl2 helps enzymes function properly. The right amount is crucial: too little MgCl2 can lead to weak or failed amplification, while too much can cause non-specific amplification. PCR Master Mixes usually contain sufficient magnesium chloride, but adjustments may be needed in certain cases (like when compensating for PCR inhibitors in DNA extracts).