To establish a semiquantitative model for the gene chip assay of SARS-CoV, a serial 10-fold dilution of SARS-CoV RNAs was amplified by MRT-PCR and hybridized to gene chips .

PCR-Machines are classified depending on the capacity of PCR used such as Nested PCR or Reverse Transcriptase PCR (RT-PCR ), or Multiplex RT PCR.