Detection of Clonal Rearrangement of the T-cell Receptor Gamma Gene by Polymerase Chain Reaction and Single-strand Conformation Polymorphism (PCR-SSCP).
Background: Diagnosis of T-lymphoid neoplasms frequently requires molecular studies of T-cell receptor (TCR) gene rearrangements. The Southern blot technique traditionally used for these analyses lacks the sensitivity and speed necessary for the routine clinical laboratory. The authors have developed a method using polymerase chain reaction (PCR) amplification with single-strand conformation polymorphism (SSCP) analysis that is rapid, sensitive, and semiautomated. Methods and Results: Polymerase chain reaction of the TCR gamma gene is done with consensus primers to the V and J regions. Amplicons thus include the N region, which serves as a marker of clonal T-cell population. Clonal populations having identical N-region sequences are identified by SSCP analysis, using a semiautomated electrophoresis system with silver staining for gel visualization. A series of 46 DNA samples from normal controls and various hematopoietic malignancies was comparatively analyzed by both Southern blot of the TCR beta locus and PCR-SSCP of the of the TCR gamma gene. The PCR-SSCP technique was rapid and reproducible, and detected clonal T-cell populations constituting 1% of the cell sample: The PCR-SSCP technique detected clones in eight cases that were negative by Southern blot. Conclusions: PCR-SSCP analysis of the TCR gamma gene is a rapid and sensitive method for the detection of clonal T-cell populations.