Behavioural visual acuity of wild type and bcl2 transgenic mouse

Since the advent of gene manipulating techniques, it has become increasingl y important to study the neural functional properties of the mouse. The bcl 2 gene has a powerful inhibitory action on naturally occurring cell death. As a consequence the brain of bcl2 overexpressing mouse is 1.5 times bigger than the brain of a wild type animal and the retina has more than twice th e ganglion cells than normal (Martinou, Dubois-Dauphin, Staple, Rodriguez, Frankowski, Missotten, Albertini, Talabot, Catsicas, Pietra, & Huarte (1994 ). Neuron, 13. 1017-1030). Since in most mammals the upper limit of behavio ural visual acuity is imposed by ganglion cells density, the visual acuity should be higher in bcl2 mice than in wild type mice. We measured behaviour al visual acuity in wild type and transgenic mice and, contrary to the expe ctation, we found it to be of the same order (0.5-0.6 c/deg) in the two gro ups of animals, indicating that an increase in ganglion cells density is no t effective in improving visual resolution. (C) 1998 Elsevier Science Ltd. All rights reserved.