BACKGROUND: Evidence suggests that the angiotensinogen (AGT) gene is involved in depression. The aim of this paper is to examine the association between the AGT M235T polymorphism and symptoms of depression in two independent populations; a population-based study, and a family-based study. METHODS: Symptoms of depression were scored using the Centre of Epidemiological Studies Depression Scale (CES-D) and compared between the MM, MT, and TT genotype groups. The extent to which AGT M235T explains the heritability of the scores was examined using a variance components analysis. RESULTS: A significant relationship between the AGT M235T polymorphism and CES-D scores was found in men in both populations. The heritability estimate was 32%. The AGT genotype contributed to 1% of the total variance of the CES-D scores. CONCLUSION: Our findings suggest that the AGT gene is involved in the aetiology of symptoms of depression in men.