Aims: We aimed to investigate the gene expression of transforming growth factors (TGFB1, TGFB2, TGFB3) in peripheral blood mononuclear cells (PBMCs) isolated from the blood of patients with unruptured intracranial aneurysms (UIAs) and ruptured intracranial aneurysms (RIAs), and from a control group. The gene discussed is TGFB1; the disease is Dilatation of the cerebral artery.