We observed that light preference index was significantly decreased to 7.25 and 10.25 in AD model flies [GMR-GAL4-UAS-TauWT/+ and GMR-GAL4-UAS-Aβ42(Human)/+, respectively] as compared to GMR-GAL4/+ flies, which had a light preference index of 17 (Fig. 2J). This evidence concerns the gene LGALS4 and Alzheimer disease.