TNF and brain infarction: Genetic linkage studies have investigated the association of polymorphisms of the TNF-alpha and TNF-beta genes with sudden SNHL comparing 97 SSNHL patients and 587 controls and found that the TNF-beta +252 A− ⟶ G polymorphism which is associated with increase in production of this cytokine was significantly increased in patients with SSNHL [60], a locus, which had previously been linked to cerebral infarction [61].