Essential hypertension is a major risk factor for cardiovascular disease in humans, and originates from both genetic and environmental factors. Data from animal and more recently human studies have indicated the presence of a gene influencing blood pressure on human chromosome 17. This study tested for linkage of markers located on chromosome 17q to essential hypertension in African Caribbean hypertensive families. No support of linkage was found between the markers studied and hypertension, however only genes of a lamda sib value of less than 1.8 could be excluded.