Inheritance of jal and 93 microsatellite markers, tested for goodness-of-fit with an independent-assortment model. Each microsatellite marker tested is represented by a single bar positioned on the horizontal axis to show its approximate location in the mouse genome. Markers from odd chromosomes are in black, those from even chromosomes are in blue. Results are plotted as negative log-transformed P values calculated by the chi-squared method (with 1 degree of freedom). Bars descend below the baseline for those markers where more recombinant types (i.e., jal inherited from the F1 mother together with a C57BL/6-derived marker allele, or jal+inherited with a C3H/HeJ-derived marker) than parental types (jal inherited from the F1 mother together with a C3H/HeJ-derived marker allele, or jal+inherited with a C57BL/6-derived marker) were observed in a set of 44 family members initially typed. Additional mice (up to all 103 in the backcross panel) were typed for markers that showed a surplus of parental types such that goodness-of-fit testing with the expected 1:1 ratio gave P < 0.1. Only markers from proximal Chr 2 showed a significant (above the orange line, where P < 0.05) or highly significant (above the red line, where P < 0.01) excess of parental types, indicative of linkage with jal.