AptaHotTaq, a HotStart polymerase, employs DNA-aptamers instead of antibodies to halt polymerase activity at ambient temperatures. These aptamers dissociate reversibly from the enzyme above 50C, enabling convenient room-temperature assembly of PCR reactions that activate during normal cycling. With AptaHotTaq, fragments up to 5 kb can be amplified. The recombinant Taq polymerase offers high specificity, yielding PCR products free of unspecific products and primer-dimers, making it suitable for amplifying complex genomic and cDNA templates. The polymerase comes with three different 10x buffers (with and without MgCl2) and additional MgCl2 for universal application.