We have studied an insertion/deletion dimorphism in the human angiotensin-converting enzyme gene amongst UAE nationals from the Abu Dhabi Emirate. Our findings show lack of association between the I/D allele marker system and clinical diagnosis of essential hypertension, suggesting that variations of the angiotensin-converting enzyme gene do not play a major role in the determination of elevated blood pressure in this Arab population. This agrees with results reported on other ethnic groups.