DNA extraction from paraffin-embedded tissues.

In routine histopathology, most tissues are fixed in formalin and embedded in paraffin for long-term preservation. DNA can be extracted from these tissues for subsequent molecular analysis by amplification methods. We describe herein a protocol for DNA preparation from paraffin-embedded tissues based on published procedures (1-3). In brief, tissue sections are placed into microfuge tubes, then deparaffinized with xylene. The xylene is removed with ethanol washes, and the tissue is treated with proteinase K to make DNA available for amplification.