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BMC Cardiovascular Disorders 2004, 4:20    [Original Document Available at]

Research article

A common genetic factor underlies hypertension and other cardiovascular disorders

Frances MK Williams , Lynn F Cherkas , Tim D Spector and Alex J MacGregor,
Twin Research and Genetic Epidemiology Unit, St Thomas' Hospital, London SE1 7EH, UK
Department of Medicine, University of East Anglia, Norwich NR4 7TJ, UK


Background Certain conditions by blood vessel occlusion or vascular spasm have been found to together in epidemiological studies. However the biological causes for these associations controversial. This study used a classical twin design to examine whether these conditions are through environmental exposures or by a common underlying genetic propensity to vasospasm.

Methods We the association between hypertension, migraine, Raynaud's phenomenon and coronary artery disease in twins from a national register. Phenotype status was using a questionnaire and the genetic and environmental association between phenotypes was estimated through variance components analysis.

Results Responses were from 2,204 individuals comprising 525 monozygotic and 577 dizygotic pairs. There was a significant genetic contribution to all four traits with heritabilities ranging from 0.34 to 0.64. Multivariate model-fitting demonstrated that a single common genetic factor the four conditions.

Conclusions We have confirmed an association between hypertension, migraine, Raynaud's phenomenon and coronary artery disease, and that a single genetic factor underlies them. The demonstration of a shared genetic factor explains the association between them and weight to the theory of an predisposition to vasospasm.