Analysis of beta-CCM induced seizures in three inbred strains of mice, ABP/Le, C57BL/6J and C57BL/6ByJ, and their F1s and F2s progeny, allowed identification of a putative seizure susceptibility controlling locus on chromosome 9 near the short-ear locus. The involvement of a gene in the medial segment of this chromosome in both seizure activity and GABA-controlled behaviour is discussed.