Its feasibility was limited until the discovery of the heat-resistant Taq polymerase.  
Life Sciences and Illumina use it for DNA sequencing, while other companies use its namesake hybridization assays for the early diagnosis of certain diseases. It comes in asymmetric, allele-specific, hot-start, and methylation-specific varieties, although in all these variations the general procedure of breaking double-stranded DNA into single-stranded  ones for 3‘ end primer addition holds. Its feasibility was limited until the discovery of the heat-resistant Taq polymerase.  FTP, name this DNA amplification procedure that doubles the amount of DNA per cycle, a method invented in 1983 by  Kary Mullis.
Life Sciences and Illumina use it for DNA sequencing, while other companies use its namesake hybridization assays for the early diagnosis of certain diseases.
Polymerase Chain Reaction)