Homozygotes display hyperactivity, a slight vibration or shakiness, and have tonic-clonic seizures beginning at two to three months of age. Heterozygotes have no obvious phenotype and do not usually have seizures.
The Ap3b2m1J mutation arose spontaneously in the C57BL/6J inbred strain in the laboratory of Dr. Wayne Frankel at The Jackson Laboratory. It has been maintained on this coisogenic background and in 2012 sperm was cryopreserved from heterozygous males.
|Allele Name||mutation 1, Jackson|
|Gene Symbol and Name||Ap3b2, adaptor-related protein complex 3, beta 2 subunit|
|Strain of Origin||C57BL/6J|
|Molecular Note||This spontaneous mutation has a 2 base pair (GT) deletion in Chromosome 7 base pairs 88,618,348 and 88,618,349, which falls in exon 15 and is predicted to cause a frameshift and stop codon at amino acid 572. Western blot analysis failed to detect this protein in homozygotes and detected only half-normal levels in heterozygotes.|