Dissecting the Genetics of Stroke

Stroke is a leading cause of death and disability in the Western world. It is a complex disease resulting from environmental factors and genetic factors, as well as gene-gene and geneenvironment interactions. Many studies have attempted to unravel the genetic aetiology of stroke, but results have been inconsistent. Most have used the candidate gene approach, but genome-wide linkage analyses have also been performed. Recently, results of genome-wide association studies have been reported, however, this approach has not yet been used to study the genetics of stroke. Stroke is a heterogeneous disease, which can be subtyped into ischaemic stroke (80%) and haemorrhagic stroke (20%), with diff erent underlying pathways. In order to reduce the complexity of stroke, intermediate phenotypes have been studied, such as hypertension, carotid atherosclerosis and cerebral white matter lesions. Another approach has been to study stroke in a genetically isolated population.