STUDIES ON WILD HOUSE MICE-VI - DIFFERENTIAL-EFFECTS OF THE Y-CHROMOSOME ON INTERMALE AGGRESSION

The aim of this study is to determine the effects of different parts o f the Y chromosome of wild house mice on aggression. To reach this goa l, intercrosses were made between two selection lines for attack laten cy (SAL and LAL) and their congenic strains (SAL.LY and LAL.SY). This procedure resulted in F, hybrids that carried the same autosomes, but differed in their X chromosome and the two different parts of their Y chromosomes, the different parts of the Y chromosome being a recombini ng part called the pseudoautosomal region (PAR) and a non-recombining part (non-PAR). We conclude that both parts of the Y chromosome contri bute slightly but significantly to variation in aggression. The major effect is accomplished by the PAR of the aggressive parent; a mirror e ffect is achieved by the non-PAR of the aggressive parent in interacti on with the PAR. (C) 1994 Wiley-Liss, Inc.