UNC5C and memory impairment: Behavioral studies were conducted on 9-month and 12-month-old Unc5c+/+ and Unc5cKI/KI mice but did not yield any conclusive evidence of hippocampal memory impairment in the Unc5cKI/KI mice (data not shown), probably because the neuronal loss just begins around that age causing behavioral deficits to manifest much later.