COMPARISON OF FORMALIN, ETHANOL, AND HISTOCHOICE FIXATION ON THE PCR AMPLIFICATION FROM PARAFFIN-EMBEDDED BREAST-CANCER TISSUE

The polymerase chain reaction (PCR) has been successfully employed for the laboratory analyses of genetic and infectious disorders using DNA extracted from paraffin-embedded tissues. However, fixative type and fixation time influenced PCR reactions and in some circumstances ampli fication fragments could not be efficiently generated. In this study, we determined the effects of three commonly used fixatives including e thanol, formalin and Histochoice, on the PCR amplification of DNA from paraffin-embedded breast cancer tissue. The effect of fixatives and f ixation times was measured by the ability of the extracted DNA to serv e as a template for the amplification of 280 and 530 base pair DNA fra gments. On amplifying DNA, positive reactions were uniformly seen in t he ethanol specimens. The next best fixative was Histochoice with posi tive results almost constantly observed in the PCR reactions performed . Formalin fixation sometimes compromised DNA amplification. Our resul ts are consistent with previous reports investigating the effect of et hanol and formalin fixation on DNA amplification by PCR. Moreover, thi s is the first study showing that paraffin-embedded tissues fixed with Histochoice can be efficiently used for PCR gene amplification.