Mice homozygous for the motor neuron degeneration (mnd) spontaneous mutation show onset of disease between 5 and 11 months. Disease characterics include hindlimb weakness and ataxia which progresses to severe spastic paralysis of all limbs, with death usually by 9 to 14 months. Histological examination of the nervous system of affected animals shows sudanophyllic, autofluorescent intraneuronal inclusions characteristic of human neuronal ceroid lipofuscinosis suggesting that mnd mice are models for such human disease as Batten's disease. Performance at 14-16 weeks of age in an associative learning task is significantly decreased relative to controls, thus providing an early disease phenotype for this neuronal ceroid lipofuscinosis model. (Wendt KD, et al., 2005) Males and females are equally affected and both are fertile, although breeding efficiency is reduced.
Homozygous mnd mice exhibit a retinopathy characterized by an early and progressive degeneration which primarily involves loss of photoreceptor cells and subsequently affects retinal neuronal cells (Guarneri R et al., 2004).
