Association of haptoglobin types with arterial blood pressure.

Haptoglobin (Hp ) is a haemoglobin binding a-2 globulin in serum. The genetic polymorphism of the protein is controlled by two codominant alleles, Hpl and Hp2 located on the long arm of chromosome-16, among which Hp2 is predominant. Studies have been taken up for association of haptoglobin phenotypes with several diseases. A high frequency of Hp 1-1 phenotypic patterns are found in haemolytic anaemia as compared to Hp 2-2 and Hp 2-1 (1,2). The high frequency of Hp 2-2 patterns was found in retinal detachment (3) and pulmonary adeno carcinoma (4). The influence of this serum protein on serum lipid levels (5) as well as atherosclerotic risk (6) is also well established. In another study (7), an increased risk was attributed to Hp 2-2 phenotype for essential hypertension and hypertension associated with ischaemic heart disease. Though a genetic component has long been suspected in essential hypertension, a clear definite mechanism is yet to be resolved. WHO (8) suggested a search for various biochemical genetic markers associated with high blood pressure. I report here an association of arterial blood pressure levels and haptoglobin phenotypes.