The historical standard FISH method has been used in cytogenetics laboratories for many years. These methods have been adapted for FFPE tissues. The pre-treatment steps include the following:
- To perform this standard pre-treatment portion of the assay, slides are incubated in 0.2 N hydrogen chloride (HCI) for 20 minutes and washed in deionized H2O for three minutes at room temperature.
- Slides are washed in 2X saline-sodium citrate (SSC) buffer for three minutes at room temperature.
- Slides are incubated in 1 M sodium thiocyanate pretreatment solution at 80°C for 30 minutes. The temperature is critical. All solution temperatures should be measured directly by a National Institute of Standards and Technology (NIST) certified thermometer in the solution. Do not rely on the digital reading of the water bath.
- Slides are washed in deionized H2O for one minute, then in buffer 1 for five minutes and buffer 2 for five minutes.
