Effect of fixation on the amplification of nucleic acids from paraffin-embedded material by the polymerase chain reaction

J. Ben-Ezra*, D. A. Johnson, J. Rossi, N. Cook, A. Wu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Amplification of nucleic acids from paraffin-embedded material by the polymerase chain reaction (PCR) is increasingly being used to detect viral genomes and oncogene mutations. To determine the effect of fixation on the preservation of the nucleic acids, we fixed two randomly chosen fresh pathology specimens in formalin, B-5, Bouin's, Zenker's, ethanol, and Omnifix for 6, 24, 48, 72, and 168 hr (1 week), and then embedded the tissue in paraffin. Oligonucleotide primers specific for the cytoplasmic-β-actin gene were chosen to span an intron such that amplification yielded a product of 250 BP for DNA and 154 BP for RNA. A single 6-μm section was cut from each paraffin block, deparaffinized, and then subjected to 30 rounds of amplification for either DNA or RNA. On amplifying DNA, consistent product was seen in the ethanol and Omnifix specimens up to 72 hr of fixation time, whereas variable product was seen with formalin or Zenker's fixation; all specimens fixed in Bouin's or B-5 were negative. On amplifying RNA, a product could be detected even after 1 week of fixation in ethanol or Omnifix, and after 48 hr in the formalin-fixed tissue. The Zenker's-fixed tissues gave variable results, and the Bouin's and B-5 tissues gave consistent results only after 6 hr of fixation. We therefore conclude that choice of fixative and fixation time are critical factors influencing the outcome of PCR amplification of nucleic acids from paraffin-embedded material.

Original languageEnglish
Pages (from-to)351-354
Number of pages4
JournalJournal of Histochemistry and Cytochemistry
Volume39
Issue number3
DOIs
StatePublished - 1991
Externally publishedYes

Keywords

  • Actin
  • Fixation
  • Polymerase chain reaction

Fingerprint

Dive into the research topics of 'Effect of fixation on the amplification of nucleic acids from paraffin-embedded material by the polymerase chain reaction'. Together they form a unique fingerprint.

Cite this