Phenotypic heterogeneity in the stargazin allelic series

The stargazer mutant mouse is characterized by its ataxic gait, head tossing, and absence seizures. The mutation was identified in the gamma2 subunit gene of the high voltage-dependent calcium channel, Cacng2. Subsequently, two allelic variants of star-gazer have arisen, waggler and stargazer 3J. In this study, we have compared these new alleles to the original stargazer allele. All three mutations affect the Cacng2 mRNA levels as they all arise from dis-ruptions within the introns of this gene. Our results show that the mutations cause reduced Cacng2 mRNA and protein levels. Stargazer and waggler mice have the least amount of mRNA and unde-tectable protein, whereas stargazer 3J appears to b