Michel's Transport Medium as an Alternative to Liquid Nitrogen for PCR Analysis of Skin Biopsy Specimens.

Formalin fixation and paraffin embedding are standard procedures for histopathological diagnosis and allow long-term archiving of tissue specimens. The cross-linking properties of formalin cause fragmentation of nucleic acids and reduce the sensitivity of PCR analysis. Michel's medium is a well-established transport medium used by dermatologists for biopsy transport to maintain tissue-fixed immunoreactants prior to direct immunofluorescence and immunoelectron microscopy. Here we report that Michel's medium also allows short-term preservation of DNA for PCR analysis and permits amplification of amplicons larger than 1 kb. Therefore, Michel's medium appears to be a reserve medium for performing PCR when no other samples are available.