Phenotypes Associated with This Genotype

Genotype
MGI:3607081

• Allelic Composition: Lhx8^tm1Vpa/Lhx8^tm1Vpa
• Genetic Background: B6.Cg-Lhx8^tm1Vpa

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

preweaning lethality, incomplete penetrance ( J:101205 )

• at weaning only 9% of pups are homozygous and of these only 1/3 are male

nervous system

abnormal dorsal striatum morphology ( J:101205 )

• the number of cholinergic neurons is reduced by about 80% in the caudate-putamen complex with the severity of the reduction being more severe in posterior areas and less severe in anterior areas

abnormal cholinergic neuron morphology ( J:101205 )

• the number of cholinergic neurons is reduced by about 80% in the caudate-putamen complex with the severity of the reduction being more severe in posterior areas and less severe in anterior areas

• cholinergic projection neurons are reduced in the basal forebrain by 70% overall with the reduction in posterior areas reaching 90-96%; however the number of GABA neurons is normal

• stimulus response curves in the CA1 area of the hippocampus and dentate gyrus and long term potentiation in the CA1 area of the hippocampus are normal

behavior/neurological

abnormal contextual conditioning behavior ( J:101205 )

• homozygotes spend more time freezing in the context not associated with the foot shock compared to wild-type littermates

abnormal spatial learning ( J:101205 )

• in the acquisition session in a Morris water maze homozygotes take longer to reach the platform and have longer swimming paths, in trial sessions mutants take longer to find the platform, and in probe trials mutants show no spatial bias for the target quadrant

• in a spontaneous alternation T maze test homozygotes alternate at chance levels (about 50%) unlike wild-type mice that alternate more than 70% of the time

• no difference in swim speed, horizontal or vertical activity, or motor coordination are seen

craniofacial

cleft palate ( J:101205 )

growth/size/body

cleft palate ( J:101205 )

decreased body weight ( J:101205 )

• a small but significant decrease in body weight is seen

digestive/alimentary system

cleft palate ( J:101205 )