Phenotypes Associated with This Genotype

Genotype
MGI:6783448

• Allelic Composition: Scn2a^em1Gsp/Scn2a⁺
• Genetic Background: involves: C57BL/6J * SJL/J

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

behavior/neurological

decreased anxiety-related response ( J:311772 )

• in the elevated plus maze, mice spend more time and travel longer distances in the open arms than controls indicating deceased anxiety-like behavior

• however, no differences in the number of entries to the open arms and closed arms and in time spend and distance traveled in the closed arms are seen

increased locomotor activity ( J:311772 )

• mice exhibit increased locomotion in the novel open-field environment

• however, no differences in grooming are seen

abnormal social investigation ( J:311772 )

• in a modified 3-chamber social interaction test, males do not show habituation to the now familiar mouse and continue to spend more time with the familiar mouse than controls

abnormal response to social novelty ( J:311772 )

• in the 3-chamber social interaction test, males spend more time with the novel mouse than with a novel object compared to controls and travel a higher distance in the zone around the novel mouse

nervous system

abnormal action potential ( J:311772 )

• the threshold to elicit action potentials in cultured forebrain pyramidal neurons is higher than in wild-type neurons

• pyramidal neurons show reduced amplitude of the action potential

• however, for a stimulus that elicits a maximal amplitude action potential, a difference in action potential amplitude is not seen in pyramidal neurons suggesting that the reduced action potential amplitude is mainly from the reduced Na+ channel current amplitude

abnormal CNS synaptic transmission ( J:311772 )

• forebrain neurons from P1-P3 pups cultured for 5-7 days exhibit reduced peak current density, with an approximate 38% reduction in Na+ channel current density in cortical pyramidal (excitatory) neurons

• a decrease in the number of spikes elicited from cortical neurons across a range of stimulation intensities and a longer latency to first spike are seen, indicating that neuronal firing is reduced in pyramidal neurons, leading to a reduction in excitatory input to postsynaptic neurons

• mice display no increase in neuronal activity when entering either the open or closed arm on the elevated plus maze compared to wild-type mice which show increased neuronal activity when entering the open arm and no increase when entering the closed arm

decreased excitatory postsynaptic current frequency ( J:311772 )

• frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in pyramidal neurons in layer 5/6 of the medial prefrontal cortex and in the basolateral amygdala is reduced, suggesting reduced excitatory

• however, the average spontaneous inhibitory postsynaptic current (sIPSC) frequency in pyramidal neurons in layer 5/6 of the medial prefrontal cortex and in the basolateral amygdala tends toward a decrease but does not reach significance

• sEPSC and sIPSC amplitudes are comparable to wild-type mice, indicating no postsynaptic differences

abnormal channel response ( J:311772 )

• cortical neurons exhibit reduced Na(v) channel current

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
autism spectrum disorder		DOID:0060041		J:311772