Polymerase chain reaction denaturing gradient gel electrophoresis (PCR/DGGE)-based detection of clonal T-cell receptor gamma gene rearrangements in paraffin-embedded cutaneous biopsies in cutaneous T-cell lymphoproliferativediseases

Polymerase chain reaction (PCR)-based amplification of T-cell receptor (TCR )-gamma genes is a novel technique that can detect a clone of T cells compr ising less than 1% of the total T cells in a lymphoid infiltrate(1). Beside s greater sensitivity than Southern blotting, this technique can be perform ed with smaller quantities of lower molecular weight genomic DNA as templat e. We retrospectively analyzed 12 paraffin-embedded biopsies of cutaneous T -cell lymphoma (CTCL), 1 case suspicious for CTCL, 1 case of granulomatous slack skin, and 8 cases of inflammatory skin diseases to determine if PCR-d enaturing gradient gel electrophoresis (PCR-DGGE) analysis can detect TCR-g amma gene rearrangements on paraffin-embedded specimens. We were able to am plify V gamma 1-8 TCR sequences in each case and detected a dominant clone in 9 of 12 cases of CTCL and ill granulomatous slack skin. We analyzed V ga mma 9 sequences in 9 cases of CTCL and detected a dominant clone in 4 cases . This study demonstrates that PCR-DGGE can easily be applied retrospective ly to cutaneous biopsies of lympho-proliferative diseases when fresh tissue is not available.