However, this hypothesis has been controversial in human research, in that no significant increase in blood BDNF levels were found after stroke [27], and associations between the BDNF met allele and ischemic stroke outcomes were not found to be significant [6], [7], although significant associations have been found in aneurismal subarachnoid haemorrhage [8], [9]. The gene discussed is BDNF; the disease is subarachnoid hemorrhage.