3214127 mPer1 mouse Per1 8 3214126 mPer1 mouse Period1 8 3214129 mPer1 mPeriod 1 2 3214128 mPer1 mice lacking the Period-1 1 3214131 mPer1 mouse Period1 gene 1 3214130 mPer1 mutation in the Period 1 1