Genetics of cerebral hemorrhage and microbleeds

Intracerebral haemorrhage (ICH) is the least treatable and often fatal form of stroke. Literature data suggest a strong familial contribution to ICH. The identification of genetic factors with a role in ICH could enhance the understanding of the pathogenesis of hemorrhagic brain injury leading to new treatment and prevention approaches with the final goal of identifying high risk individuals in which genetic pattern may influence clinical and therapeutical decisions. Herein, we provide an updated review on genetic factors associated with occurrence and outcome of ICH. Except for monogenic disease which account for a minor proportion of hemorrhages, most of hemorrhagic stroke heritability is believed to be polygenic. However, the results of candidate gene studies did not show significant results except for the association between apoE genotype and ICH, which has been replicated in large population studies. These data may support the hypothesis that the risk that can be attributed to each of these polymorphisms taken individually is still moderate and some relatively common variants could contribute in determining the disease acting in synergy with other genetic factors.