The animals exhibiting severe ataxia with staggering gait and tremor at about 14 days of age, and die around 4 weeks of age. The cerebellum of the mutants shows severe hypoplasia with the reduction of the molecular and granular layers and malposition of Purkinje cells in the white matter.
The abnormal pathological changes are also detected in the cerebrum, including the absence of a well-defined outer molecular layer, no typical lamination, and irregular cell arrangement in the hippocampus.