Phenotypes associated with this allele

• Allele Symbol: Chrna4^tm2.1Dra
• Allele Name: targeted mutation 2.1, John Drago
• Allele ID: MGI:3767042
• Summary: 3 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
ht1	Chrna4^tm2.1Dra/Chrna4^+	B6.129S1-Chrna4^tm2.1Dra	MGI:3767046
ht2	Chrna4^tm2.1Dra/Chrna4^+	involves: 129S1/Sv * C57BL/6 * CD-1	MGI:3767045
ht3	Chrna4^tm2.1Dra/Chrna4^+	involves: 129S1/Sv * CD-1	MGI:3767044

Genotype
MGI:3767046

ht1

• Allelic Composition: Chrna4^tm2.1Dra/Chrna4⁺
• Genetic Background: B6.129S1-Chrna4^tm2.1Dra

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

behavior/neurological

behavior/neurological phenotype ( J:125305 )

N • mice do not display spontaneous or handling -induced seizures

abnormal behavioral response to addictive substance ( J:125305 )

• in response to injection of 2 mg/kg of nicotine, mice display three distinct stereotypic behaviors (saccadic behavior, forelimb dystonia, Straub tail) collectively termed DAC

• Background Sensitivity: compared to mice on a mixed 129S1/Sv and CD1 background forelimb dystonia is less severe, manifesting as forelimb suppination with clenched fists and rhythmic forelimb retraction

• Background Sensitivity: compared to mice on a mixed 129S1/Sv and CD1 background saccadic behavior is significantly reduced

• the DAC response is not associated with epileptiform changes on electroencephalograms

impaired behavioral response to nicotine ( J:125305 )

• mice display less severe nicotine induced seizures compared to wild-type mice

Genotype
MGI:3767045

ht2

• Allelic Composition: Chrna4^tm2.1Dra/Chrna4⁺
• Genetic Background: involves: 129S1/Sv * C57BL/6 * CD-1

behavior/neurological

behavior/neurological phenotype ( J:125305 )

N • mice do not display spontaneous or handling -induced seizures

abnormal behavioral response to addictive substance ( J:125305 )

• in response to injection of 2 mg/kg of nicotine, mice display three distinct stereotypic behaviors (saccadic behavior, forelimb dystonia, Straub tail) collectively termed DAC

• the DAC response is not associated with epileptiform changes on electroencephalograms

• on a mixed 129S1/Sv, C57BL/6 and CD1 background 94% of females and 89% of males display DAC after nicotine injection

• females display more severe forelimb dystonia compared to males

• pretreatment with a nicotinic channel antagonist does not disrupt the DAC response following injection of 8 mg/kg nicotine but does inhibit seizure responses to this dose of nicotine

• pretreatment with carbamazepine (a sodium channel blocker used to treat autosomal-dominant nocturnal frontal lobe epilepsy) does inhibit the dystonic response to nicotine

impaired behavioral response to nicotine ( J:125305 )

• mice display less severe nicotine induced seizures compared to wild-type mice

Genotype
MGI:3767044

ht3

• Allelic Composition: Chrna4^tm2.1Dra/Chrna4⁺
• Genetic Background: involves: 129S1/Sv * CD-1

behavior/neurological

behavior/neurological phenotype ( J:125305 )

N • mice do not display spontaneous or handling -induced seizures

abnormal behavioral response to addictive substance ( J:125305 )

• in response to injection of 2 mg/kg of nicotine mice display three distinct stereotypic behaviors (saccadic behavior, forelimb dystonia, Straub tail) collectively termed DAC

• the DAC response is not associated with epileptiform changes on electroencephalograms

• Background Sensitivity: on a mixed 129S1/Sv and CD1 background forelimb dystonia and saccadic behavior are more pronounced than in mice on an inbred C57BL/6 background

• on a mixed 129S1/Sv and CD1 background all females and 75% of males display DAC after nicotine injection

• females display more severe forelimb dystonia and Straub tail compared to males

• pretreatment with a low dose of nicotine (0.1 mg/kg) blocks the development of DAC in response to 2 mg/kg nicotine given 10 min later

impaired behavioral response to nicotine ( J:125305 )

• mice display less severe nicotine induced seizures compared to wild-type mice