KCNAB2 and Seizure: Seizures and a reduced lifespan have also been described in Kcna1 null mice, in which the expression of the Kv1.1 subunit is abolished [18], as well as in Kcnab2 null mice [19], lacking the modulatory subunit beta 2, which co-distributes extensively with Kv1.1 and Kv1.2 in the adult rat brain [11].