Albino mice as an animal model for infantile nystagmus syndrome.
OBJECTIVE
Individuals with oculocutaneous albinism are predisposed to visual system abnormalities affecting the retina and retinofugal projections, which may lead to reduced visual acuity and Infantile Nystagmus Syndrome (INS). Due to absence of an established mammalian animal model, mechanisms underlying INS remain elusive. In this study, we screened wild-type mice of varying pigmentation for ocular motor abnormalities in order to identify a possible mouse model for INS.


METHODS
Three albino mouse strains (CD1, BALB/c, DBA/1), and two normally pigmented strains (129S6, C57BL/6) were screened using infrared oculography. Varying visual stimuli (black or white background, stationary pattern, optokinetic, i.e., horizontally rotating pattern) were displayed to the full (fVF) or anterior visual field (aVF) of the restrained mouse.


RESULTS
We found spontaneous nystagmus, specifically jerks and oscillations, in albino mice under all experimental conditions. Median eye velocity was between 0.8 and 3.4 deg/s, depending on the strain. In contrast, the eyes in pigmented mice were nearly stable with a median absolute eye velocity of below 0.4 deg/s. In albino mice, fVF optokinetic stimuli elicited an optokinetic response (OKR) in the correct direction, albeit with superimposed oscillations. However, aVF optokinetic stimuli evoked reversed OKR in these strains, a well known feature of INS.


CONCLUSIONS
Based on our results, we endorse the investigated albino mouse strains as new animal models for INS.
Lab for Retinal Cell Biology, Department of Ophthalmology, Zurich University Hospital, Zurich, Switzerland. ghislaine.traber@phima.com
Ghislaine L
GL
Traber
Chien-Cheng
CC
Chen
Ying-Yu
YY
Huang
Marcella
M
Spoor
Jeanine
J
Roos
Maarten A
MA
Frens
Dominik
D
Straumann
Christian
C
Grimm
D016115:Albinism, Oculocutaneous / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D000818:Animals; D004195:Disease Models, Animal; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D020417:Nystagmus, Congenital / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D017120:Nystagmus, Optokinetic / Q000502:physiology