Phenotypes associated with this allele

• Allele Symbol: Chd8^tm1Kei
• Allele Name: targeted mutation 1, Keiichi I Nakayama
• Allele ID: MGI:3530648
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Chd8^tm1Kei/Chd8^tm1Kei	involves: C57BL/6	MGI:3531401
ht2	Chd8^tm1Kei/Chd8^+	involves: 129P2/OlaHsd * C57BL/6J	MGI:7413047

Genotype
MGI:3531401

hm1

• Allelic Composition: Chd8^tm1Kei/Chd8^tm1Kei
• Genetic Background: involves: C57BL/6

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

mortality/aging

embryonic lethality, complete penetrance ( J:92968 )

• homozygous null embryos were found at E8.5 but most were resorbed by E9.5

embryo

increased ectoderm apoptosis ( J:92968 )

• cells with condensed nuclei and pronounced cell apoptosis were apparent in the ectoderm-like layer of E7.5 homozygous null embryos

• however, increased apoptosis was not observed at E6

embryonic growth arrest ( J:92968 )

• homozygous null embryos appeared retarded as early as E5.5 and almost arrested after E6.5

absent mesoderm ( J:92968 )

• formation of the mesoderm was not observed at E7.5

• embryos developed into an egg cylinder consisting of only the ectoderm and visceral endoderm

failure of primitive streak formation ( J:92968 )

• formation of the primitive streak was not observed at E7.5

abnormal inner cell mass morphology ( J:92968 )

• the inner cell mass of E3.5 null embryos developed poorly and formed colonies incompletely after 4-5 days in culture

• however, blastocysts grown in culture produced normal trophoblast giant cells

inner cell mass degeneration ( J:92968 )

• the inner cell mass of E3.5 null embryos collapsed and disappeared after 6 days in culture

cellular

increased ectoderm apoptosis ( J:92968 )

• cells with condensed nuclei and pronounced cell apoptosis were apparent in the ectoderm-like layer of E7.5 homozygous null embryos

• however, increased apoptosis was not observed at E6

Genotype
MGI:7413047

ht2

• Allelic Composition: Chd8^tm1Kei/Chd8⁺
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6J

nervous system

increased brain weight ( J:235128 )

• brain weight is increased at E18.5

increased prepulse inhibition ( J:235128 )

• mice exhibit increased prepulse inhibition for 74- or 78-dB prepulses before a 120-dB startle stimulus

behavior/neurological

increased anxiety-related response ( J:235128 )

• mice spend less time in the light chamber for the light-dark transition test, in the open arms for the elevated plus-maze test, and in the center of the open-field indicating increased anxiety

decreased startle reflex ( J:235128 )

• mice show a lower acoustic startle response

abnormal social investigation ( J:235128 )

• mice show reduced number of social contacts in the social-interaction test but an increase in the duration per contact, resulting in an increase in total contact time

• however, the total duration of active contacts such as sniffing and following behavior is reduced

growth/size/body

megacephaly ( J:235128 )

• brain weight and volume are increased indicating macrocephaly

digestive/alimentary system

decreased intestine length ( J:235128 )

• mice have shorter intestine

abnormal intestinal transit time ( J:235128 )

• mice tend to show slower intestinal transit

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
autism spectrum disorder		DOID:0060041		J:235128