INSTABILITY AT THE H-RAS MINISATELLITE IN HUMAN ATHEROSCLEROTIC PLAQUES

The development of atherosclerotic plaques is characterised by the acc umulation of lipids and the proliferation of smooth muscle cells. At t he subcellular level, the abnormal expression of cytokines and growth factors, as well as the presence of transforming oncogenes, has been r ecognised and associated with the disease. The aim of the present stud y was to investigate whether instability at a minisatellite region loc ated downstream of the H-ras proto-oncogene possessing enhancer activi ty, is a detectable phenomenon in atherosclerotic plaques. Thirty spec imens were analysed by polymerase chain reaction (PCR) in order to rev eal alterations of the repetition number and by restriction fragment l ength 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, alt erations of the repetition number of the core were detected in 5 (17%) cases. Our results suggest that instability at the H-ras minisatellit e may be associated with development of the disease.