I extract dna from duck whole blood. Blood samples are preserved in edta. After adding protein k and lysis solution, blood is coagulated. It make me unable to extract. I don't know why. It's my final thesis. Anybody help me!
I would recommend pelleting down the cells and washing them 2X in PBS -/- and then trying the proteinase K. If that does not work, you will want to use a RBC lysis buffer to remove the red cells.