Phenotypes Associated with This Genotype

Genotype
MGI:3639581

• Allelic Composition: Zic2^Ku/Zic2^Ku
• Genetic Background: C3.CAnNCrl-Zic2^Ku

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

mortality/aging

embryonic lethality during organogenesis, complete penetrance ( J:86841 )

• all homozygotes are dead or dying at E13.5

cellular

increased ectoderm apoptosis ( J:138862 )

• significant increase in the number of apoptotic cells in the ectoderm at E7.5

nervous system

decreased neural crest cell number ( J:86841 )

• reduction in the number of neural crest cells produced both in the cranial and trunk regions

• the posterior limit of crest is shifted rostrally relative to wild-type

• the number of crest cells following the subectodermal or the ventrolateral pathways are significantly reduced while the ventromedial pathway is only affected in the younger embryos, however migration is normal

delayed caudal neuropore closure ( J:86841 )

• exhibit delayed posterior neuropore closure

incomplete rostral neuropore closure ( J:86841 )

• open cranial neural tube at E9.5

spina bifida ( J:138862 )

decreased rhombomere 3 size ( J:86841 )

• rhombomere 3 is reduced in size

decreased rhombomere 5 size ( J:86841 )

• rhombomere 5 is reduced in size

abnormal forebrain development ( J:138862 )

• abnormal forebrain at E9.5

• ventral forebrain tissue between the optic eminences is reduced

holoprosencephaly ( J:138862 )

• mice exhibit a typical spectrum of holoprosencephaly phenotypes

• remnants of forebrain tissue are rostral of the eye and this tissue remains as a single mass of neural cells with no interhemispheric fissure

exencephaly ( J:138862 )

• most E12.5 embryos have exencaphaly

craniofacial

proboscis ( J:138862 )

growth/size/body

proboscis ( J:138862 )

cardiovascular system

hematoma ( J:86841 )

• exhibit hematomas of the forebrain

limbs/digits/tail

curly tail ( J:138862 )

• looped tail

embryo

increased ectoderm apoptosis ( J:138862 )

• significant increase in the number of apoptotic cells in the ectoderm at E7.5

decreased neural crest cell number ( J:86841 )

• reduction in the number of neural crest cells produced both in the cranial and trunk regions

• the posterior limit of crest is shifted rostrally relative to wild-type

• the number of crest cells following the subectodermal or the ventrolateral pathways are significantly reduced while the ventromedial pathway is only affected in the younger embryos, however migration is normal

delayed caudal neuropore closure ( J:86841 )

• exhibit delayed posterior neuropore closure

incomplete rostral neuropore closure ( J:86841 )

• open cranial neural tube at E9.5

spina bifida ( J:138862 )

decreased rhombomere 3 size ( J:86841 )

• rhombomere 3 is reduced in size

decreased rhombomere 5 size ( J:86841 )

• rhombomere 5 is reduced in size

abnormal notochord morphology ( J:138862 )

• disruption of the anterior notochord at E9.5

abnormal prechordal plate morphology ( J:138862 )

• marker analysis indicates aberrant prechordal plate development, however prechordal plate development is initiated in mutants

• marker analysis indicates that prechordal plate cells are specified correctly but that the node of the mid-gastrula embryo is defective

abnormal primitive node morphology ( J:138862 )

• at the late streak stage, the organizer region (node) is abnormal

vision/eye

abnormal eye distance/ position ( J:138862 )

• all E12.5 embryos show abnormally spaced eyes with dysmorphologies ranging from hypotelorism to cyclopia

cyclopia ( J:138862 )

• 58% of embryos show cyclopia

• 5% (one embryo) shows two eyes fused at the midline (synophthalmia)

ocular hypotelorism ( J:138862 )

• 37% of embryos show hypotelorism

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
holoprosencephaly 5		DOID:0110878	OMIM:609637	J:138862