Phenotypes Associated with This Genotype

Genotype
MGI:3698855

• Allelic Composition: Htt^tm2Msl/Htt^tm2Msl
• Genetic Background: involves: 129S1/Sv * C57BL/6J

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

nervous system

abnormal striatum morphology ( J:79137 )

• nuclear microaggregates of mutant protein in striatal neurons are rare at 4 months of age but become widely distributed at 6 months of age and nuclear inclusions do not appear until 18 months of age; microaggregates are predominately found in the striosomal compartment

• total volume of the striatum is significantly reduced in 18 and 26-month old mutants, however show normal numbers of medium spiny neurons which results in increased density of neurons in the striatum

abnormal neuron physiology ( J:76018 )

• striatal and cortical neurons display more rapid and increased swelling to N-methyl-D-aspartate (NMDA) than controls, but not to alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) or kainate (KA), indicating increased sensitivity to NMDA

• intracellular recordings show that resting membrane potentials of striatal neurons are significantly more depolarized than in controls

behavior/neurological

increased vertical activity ( J:79137 )

• exhibit increased rearing at night at 2 months of age but not at later time points

decreased locomotor activity ( J:79137 )

• the initial increase in rearing is followed by decreased locomotion at 4 and 6 months of age

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Huntington's disease		DOID:12858	OMIM:143100	J:76018 , J:79137