Phenotypes Associated with This Genotype

Genotype
MGI:2675621

• Allelic Composition: twit/twit
• Genetic Background: D2.B6Ei/2Ei

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

mortality/aging

preweaning lethality, incomplete penetrance ( J:85479 )

• some homozygous mutants die before weaning, but others survive through adulthood

• viability was estimated at 18%

behavior/neurological

tremors ( J:85479 )

• by 2.5-3 weeks of age, a constant quivering most obvious from the abdominal-thoracic area to nose

• routine histological screening found no neurologic lesions to explain the rostral tremors

• myelination was normal

decreased grip strength ( J:85479 )

• mutants show poor ability to hold onto an edge with either their fore or hindlimbs

abnormal vocalization ( J:85479 )

• mice exhibit excessive chattering; examination of the heart, lungs, pharynx, trachea and nasal passages found no explanation for the chattering as all tissues appeared normal without infection or inflammation

growth/size/body

decreased body size ( J:85479 )

• mutants are recognizable by 2.5-3 weeks of age by their smaller body size, gaunt torso, and frailty

reproductive system

abnormal fertility/fecundity ( J:85479 )

• mice that survive are unreliable breeders