Experiment
Mouse strains C57BL/6J and DBA/2J were reciprocally crossed and the resulting F1 females from these crosses were mated to produce in the range of 1200 B6D2F2 animals. From these 1200 mice approximately 400 were tested at each of three ages 150 , 450 and 750 days. Using these mice and BXD RI lines QTL analysis was conducted for hole board activity(Hbact), head-board rears(Hbrear) , head pokes (Hp) and feacal boli (Fb). QTLs for Hbact and Hbrear mapped significantly with mouse Chromosomes , whereas Hp and Fb mapped as suggestive QTLs. A genome wide scan using 96 Mit markers was informative in mapping the behavioral traits Hbact and Hbrear to the genome. Activity was measured as the number of squares crossed in 3 min in a Hole-board and the following loci were mapped (the number following the locus is the peak cM following by the 1.5 LOD interval) Hbact1: Chr 2 peak = 73cM (57 - 85 cM), - Hbact2: Chr4 peak = 49cM (18-71 cM), Hbact3: Chr5 peak = 68 cM (50-75 cM) ,Hbact4: Chr6 peak = 46 cM (30 -74 cM), Hbact5: Chr11 peak = 28 cM (17 -38 cM), Hbact6: Chr13 peak = 44 cM (35 -73 cM), Hbact7: Chr17 peak = 18 cM (0-34 cM). The following indicates the QTL region for head-board rears(Hbrear), Hbrear1: Chr2 peak = 50 cM (31-73 cM), Hbrear2: Chr4 peak= 49 cM (17-62 cM), Hbrear3: Chr6 peak = 46 cM (32-74 cM), Hbrear4: Chr13 peak = 62 cM (44-80 cM), Hbrear5: Chr19 peak = 47 cM (25-54 cM).