Phenotypes Associated with This Genotype

Genotype
MGI:3624435

• Allelic Composition: Myo5a^d-n/Myo5a^d-n
• Genetic Background: B10.D2-H2^d/nSnJ

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

pigmentation

abnormal coat/hair pigmentation ( J:47547 )

diluted coat color ( J:47547 , J:171603 )

• mice appear gray on a nonagouti background (J:47547)

behavior/neurological

behavior/neurological phenotype ( J:171603 )

N • frequency of spontaneous eyeblink and startle response to the tone conditioned stimulus are no different from wild-type mice

abnormal eye blink conditioning behavior ( J:171603 )

• young mutants (P28-P29) exhibit impaired eyeblink conditioning while adults show similar eyeblink conditioning as wild-type mice

abnormal motor capabilities/coordination/movement ( J:47547 )

• the majority of homozygotes of both sexes reach adulthood and are fertile

impaired coordination ( J:171603 )

• on the rotarod test, both young and adult mutants fail to stay on the rod and performance was not improved even by training for 7 days as in wild-type mice

• on a fixed-bar test, both young and adult mutants are unable to stay on the bar at all

abnormal locomotor coordination ( J:171603 )

• adult mutants exhibit abnormal movements, such as occasionally lifting the tail and a tendency to waddle

ataxia ( J:171603 )

abnormal gait ( J:171603 )

• mutants develop gait abnormalities at P10-P11

• adult mutants exhibit abnormal gait, with a wider gait and a more irregular stride pattern than wild-type mice

clonic seizures ( J:171603 )

• mutants exhibit clonic seizures, which are most severe at 2-4 weeks of age, however seizures cease by 1 month of age

integument

abnormal coat/hair pigmentation ( J:47547 )

diluted coat color ( J:47547 , J:171603 )

• mice appear gray on a nonagouti background (J:47547)

growth/size/body

slow postnatal weight gain ( J:171603 )

• after the onset of neurological abnormalities around P10-P11, mutants show poor weight gain, even as adults

nervous system

clonic seizures ( J:171603 )

• mutants exhibit clonic seizures, which are most severe at 2-4 weeks of age, however seizures cease by 1 month of age

abnormal cerebellum morphology ( J:171603 )

• cerebellar weights are slightly lower than of wild-type, and these weights scarcely increase from 3 weeks of age to adulthood

• however, no gross alteration of cerebellar architecture is seen during postnatal development or adulthood

abnormal Purkinje cell dendrite morphology ( J:171603 )

• although smooth endoplasmic reticulum (SER) is present in dendrites and soma of Purkinje cells, SER rarely extends into the dendritic spines of Purkinje cells in young mice

• Purkinje cell spines lack IP3 receptors in young mutants

• adults show SER and IP3 receptors in Purkinje cell spines, however, the tubular SER networks form poorly within the Purkinje cell spines and IP3 receptors are not as abundant as in wild-type mice

reduced long-term depression ( J:171603 )

• long term depression (LTD) at parallel fiber-Purkinje cell synapses is abolished in young mice, however LTD is restored in adults

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Griscelli syndrome type 1		DOID:0060832	OMIM:214450	J:171603