Hi Eugene

I am still working on some approaches for the extraction of DNA and RNA from formalin-fixed and paraffin-embedded tissues, but as a result of our experience with Toxoplasma gondii, Trypanosoma cruzi, Yellow fever and Dengue Fever virus you could do this:

1.- Deparaffinization of 6 to 10 sections (5-7 um thick) in a 1,5 mL vial. A routine of 5 washes and centrifugations (13,600 x g  for 5 minutes) with xylene is enough to remove the paraffin

2.- Wash out the xylene with absolute etanol (HPLC grade) (5 washes and centrifugations) are enough to remove all the xylene

3.- Dry out the biological material (pellet) in a SpeedVac at low temperature for 30-60 minutes depending on the number samples and the amount of biological material per sample

4.- Digest the biological sample with Proteinase K (1 mg/ml) in a buffer containing EDTA, SDS and Sarcosyl for 24-48 hours depending on the amount of biological material

5.- Extract the DNA with the QIAGEN kit for FF- and PE-tissues, or inactivate the Proteinase K at 98 ºC for 10 minutes before the use of this extract in your PCR routine

Good luck

use CTAB method is suitable for most DNA extraction from the organisms 

Hi Oadi

I have used CTAB methods with mycobacteria but I do not have experience with these methods working on FF- and PE-tissue. I do not know if these methods are effective to break the association of proteins with nucleic acids in samples that were treated with formalin and in which occurred methylene covalent links between proteins and nucleic acids during fixing.

I think the best way is to do some testing with both methods and see which works best

We keep in touch