Instability at the H-ras minisatellite in human atherosclerotic plaques

The development of atherosclerotic plaques is characterised by the accumulation of lipids and the proliferation of smooth muscle cells. At the subcellular level, the abnormal expression of cytokines and growth factors, as well as the presence of transforming oncogenes, has been recognised and associated with the disease. The aim of the present study was to investigate whether instability at a minisatellite region located downstream of the H-ras proto-oncogene possessing enhancer activity, is a detectable phenomenon in atherosclerotic plaques. Thirty specimens were analysed by polymerase chain reaction (PCR) in order to reveal alterations of the repetition number and by restriction fragment length polymorphism (RFLP) with BstNI restriction endonuclease for the detection of point mutations within the 28 bp core repetitive element. No point mutations were found among the 30 cases tested; however, alterations of the repetition number of the core were detected in 5 (17%) cases. Our results suggest that instability at the H-ras minisatellite may be associated with development of the disease.