Genetics of Hypertension

Abstract

Despite the high prevalence of hypertension and its resulting morbidity and mortality, our knowledge of its pathogenesis remains limited. Strong evidence for a genetic role in blood pressure (BP) variability was first provided by familial segregation studies and the identification of mendelian disorders causing marked hypertension. These monogenic diseases, largely involving genes in sodium homeostatic pathways, have reinforced the Guytonian principle that BP is largely governed by renal sodium excretion. More recently, large population based genome wide association studies (GWAS) have attempted to fill in the missing heritability of the BP trait, with mixed results. Although many variants have been identified that are robustly associated with BP variability, they are mostly rare and together are responsible for a tiny percentage of total trait variability. Observations from GWAS include shared risk variants for cardiovascular and kidney disease, including polymorphisms in UMOD. Mutations in this gene are known to cause monogenic renal disease. GWAS data may be employed for pathway analysis to discover the etiology of hypertension as well providing the potential to interrogate drug responses to antihypertensive agents depending on genotype. The chapter concludes with describing future directions in BP genetics including evidence of the role of epigenetic mechanisms in BP pathogenesis. As we enter the era of whole genome sequencing, the possibility exists to discover the missing hereditability of BP variation although this technology will present its own challenges. This review contains 6 figures, 2 tables and 94 references Key words: adrenocorticotropic hormone, autosomal dominant, autosomal recessive, cytosine-phosphate-guanine, epithelial sodium channel