Phenotypes associated with this allele

• Allele Symbol: Sp8^tm2.1Aman
• Allele Name: targeted mutation 2.1, Ahmed Mansouri
• Allele ID: MGI:4455192
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
cn1	Sp8^tm2.1Aman/Sp8^tm2.1Aman Foxg1^tm1(cre)Skm/Foxg1^+	involves: 129P2/OlaHsd * C57BL/6	MGI:4455199

Genotype
MGI:4455199

cn1

• Allelic Composition: Sp8^tm2.1Aman/Sp8^tm2.1Aman; Foxg1^tm1(cre)Skm/Foxg1⁺
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

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

mortality/aging

neonatal lethality, complete penetrance ( J:160653 )

• mice die at birth

nervous system

increased neuron apoptosis ( J:160653 )

• between E10.5 and E18.5, post-mitotic neurons and neuronal progenitors exhibit an increase in apoptosis in the forebrain compared to in wild-type mice

abnormal neuronal precursor proliferation ( J:160653 )

• at E18.5, fewer BrdU+ cells are found within the upper cortical layers of the subventricular zone while more are detected in the superficial positions in the cortical plate compared to in wild-type mice

abnormal forebrain development ( J:160653 )

• at E12.5 and E15.5, mice lack the septum at the rostral level unlike wild-type mice

• mice exhibit dysgenesis of the olfactory bulb and septum, including an almost complete absence of the midline, compared with wild-type mice

• corticofugal fiber tracts do not cross the midline and instead form probst bundles and, caudally, neuronal fibers form bundles between the internal and external capsules

abnormal telencephalon development ( J:160653 )

• as determined by marker expression, dorsal ventral patterning of the medial telencephalon is altered compared to in wild-type mice

• as determined by marker expression, mice exhibit abnormal cortical arealization and thalamic innervation compared to in wild-type mice

• mice exhibit defective preplate splitting compared with wild-type mice

abnormal cortical plate morphology ( J:160653 )

• as determined by marker expression, mice exhibit abnormal cortical arealization and thalamic innervation compared to in wild-type mice

• as determined by marker expression, lower cortical layers are not correctly specified and upper cortical layer neurons are reduced compared to in wild-type mice

• mice exhibit misspecification in specific cortical neuron subtypes (Cux1+, Lhx2+, Rorb+, and Etv1+)

thin cortical plate ( J:160653 )

abnormal olfactory bulb development ( J:160653 )

• mice exhibit dysgenesis of the olfactory bulb and septum, including an almost complete absence of the midline, compared with wild-type mice

holoprosencephaly ( J:160653 )

• mild rostral

forebrain hypoplasia ( J:160653 )

abnormal lateral ventricle morphology ( J:160653 )

• the lateral ventricles are fused because of the complete disgenesis of the midline unlike in wild-type mice

abnormal brain internal capsule morphology ( J:160653 )

• aberrant bundles of Gap43+ fibers form within the internal capsule with some axons projecting ectopically towards the marginal zone and basal telencephalon unlike in wild-type mice

abnormal basal ganglion morphology ( J:160653 )

• basal ganglia consist of a single eminence with a barely discernable constriction between the lateral and medial ganglion eminence compared to in wild-type mice

telencephalon hypoplasia ( J:160653 )

• at E12.5

craniofacial

abnormal craniofacial morphology ( J:160653 )

• at midgestation

cellular

increased neuron apoptosis ( J:160653 )

• between E10.5 and E18.5, post-mitotic neurons and neuronal progenitors exhibit an increase in apoptosis in the forebrain compared to in wild-type mice

abnormal neuronal precursor proliferation ( J:160653 )

• at E18.5, fewer BrdU+ cells are found within the upper cortical layers of the subventricular zone while more are detected in the superficial positions in the cortical plate compared to in wild-type mice