Segregation of jal and five microsatellite markers on proximal Chr 2 among 374 backcross mice. The five markers typed are shown to the left of the diagram. The haplotype transmitted by the heterozygous F1 dam is depicted. Open boxes indicate A/J-derived alleles; solid boxes indicate C3H/HeJ-derived alleles. The centromere is indicated by a knob at the top of each haplotype. The number of progeny inheriting each haplotype is shown below it. Genetic distances are shown to the right. The red arrows indicate that in these recombinant mutants, the mutant jal allele must be located below D2Mit359, but above D2Mit80. The blue arrows similarly indicate that in these recombinant wild type mice, the normal jal+allele must be located below D2Mit359, but above D2Mit80.