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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID
Nacc1em1Mdif
endonuclease-mediated mutation 1, Marian DiFiglia
MGI:8172584
Summary 2 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
Nacc1em1Mdif/Nacc1em1Mdif C57BL/6-Nacc1em1Mdif MGI:8172942
ht2
Nacc1em1Mdif/Nacc1+ C57BL/6-Nacc1em1Mdif MGI:8172940


Genotype
MGI:8172942
hm1
Allelic
Composition
Nacc1em1Mdif/Nacc1em1Mdif
Genetic
Background
C57BL/6-Nacc1em1Mdif
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Nacc1em1Mdif mutation (0 available); any Nacc1 mutation (63 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• a reduction in the percentage of homozygotes (both males and females) is seen at P21, however normal numbers are seen at E17.5 and P7, indicating partial lethality between P7 and P21

growth/size/body
• weight is normal at E17.5, but P7 males and females show reduced weight
• P14 males show reduced weight, while females only show a trend towards reduced weight and P21 males and females show reduced weight indicating mice from P7 to 6 months have delayed weight gain for both males and females

behavior/neurological
• homozygotes bred beyond F6 generations exhibit hindlimb clasping; this includes 5 of 6 F8 homozygotes at 3.2 months and 19 of 20 F10 homozygotes at 2.8-3 months of age
• seizure-like behaviors appear at 7 months of age
• seizure-like behaviors include momentary or sustained freezing, whisker twitching and head bobbing and wild jumping

nervous system
• seizure-like behaviors appear at 7 months of age
• seizure-like behaviors include momentary or sustained freezing, whisker twitching and head bobbing and wild jumping

vision/eye
N
• no cataracts are seen in 1.5-5-month-old mice




Genotype
MGI:8172940
ht2
Allelic
Composition
Nacc1em1Mdif/Nacc1+
Genetic
Background
C57BL/6-Nacc1em1Mdif
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Nacc1em1Mdif mutation (0 available); any Nacc1 mutation (63 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
behavior/neurological
N
• mice exhibit normal performance in the 2 day novel object recognition test, in the Y-maze, and in grip strength, indicating normal long-term memory recall, short-term spatial working memory, and strength
• females, but not males, spend less time in the center of the open field and more time in the border, possibly indicating greater anxiety
• however, no differences in total distance traveled in the open field are seen
• male and female mice at 3 months of age, but not at P14, exhibit increased hindlimb clasping indicating that clasping develops after P14
• females at 6 months of age exhibit increased clasping
• females exhibit a shorter hindlimb stride length at 4 months of age
• however, no difference in forelimb stride length or in stride width and diagonal stride with are seen
• during SWS, males exhibit higher delta power; this occurs during the light period, when mice are mostly asleep, indicating a deeper SWS and more sleep pressure
• females spend a greater percent of time in slow-wave sleep (SWS)
• aside from this greater time in SWS for females, 24 hour circadian period analysis indicates that mice show an hourly percentage of wakefulness, SWS, and REM sleep similar to wild-type mice
• spectral power distributions of the EEG during wake-sleep cycles are similar to wild-type mice
• during REM sleep, females show a deficit in the percentage of total power associated with theta band; this occurs during the period when mice are highly awake, indicating a deficit in hippocampal synchronization
• innate ability to build nests is impaired in females
• behavioral seizures are seen in some mice starting from 7 months of age in the home cage either spontaneously or in response to handling, a sudden noise or light stimulus
• seizure-like behaviors include momentary or sustained freezing, whisker twitching and head bobbing and wild jumping

growth/size/body
• P120 and P180 males show reduced weight, while only P180 females have reduced weight, indicating that mice show sex-dependent changes in weight at some ages
• P7 females show reduced weight, but normal weight at E17.5
• however, males show normal weight at E17.5, P1, P7

nervous system
• behavioral seizures are seen in some mice starting from 7 months of age in the home cage either spontaneously or in response to handling, a sudden noise or light stimulus
• seizure-like behaviors include momentary or sustained freezing, whisker twitching and head bobbing and wild jumping
• mice show single or repetitive high-amplitude epileptiform discharges in the EEG during wakefulness and REM sleep
• during wakefulness, epileptiform discharges coincide with low EMG activity and behavioral arrest
• spectral power distribution differs between periods of epileptiform discharges and those of normal wakefulness and REM sleep, with percentage of total power reduced in the delta band (1-3 Hz) and increased in the beta band (13-30 Hz)
• males show other changes in power spectra of the bursting periods during wakefulness (gamma, 55-60 Hz) and REM sleep (theta, 4.5-10 Hz and sigma, 1-3 Hz)
• power spectra analysis of epileptiform discharges during wakefulness also shows rhythmic activity of the theta frequency range in both males and females and is associated with harmonics (at 16 and 24 Hz) characteristic of EEG hypersynchrony

vision/eye
N
• no cataracts are seen in 1.5-5-month-old mice





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last database update
03/25/2025
MGI 6.24
The Jackson Laboratory