The present invention relates to a diagnostic method for diagnosing unstable atherosclerotic plaque, a method for determining the probability of a subject suffering from a cerebrovascular disease, and a method for selecting a patient susceptible to being treated with a therapy for removing or stabilizing the carotid atherosclerotic plaque based on determining the expression level of at least one gene selected from the group of genes shown in Table 1. The invention also relates to a kit having reagents suitable for determining the expression levels of at least one gene selected from the group of genes shown in Table 1, and optionally reagents for determining the expression levels of one or more housekeeping genes, and uses of the kit.