Fine mapping of Ity2 and Ity3 loci. A schematic of the Ity2 congenics on chromosome 11 (A) and the Ity3 congenics on chromosome 1 (B). The open box represents regions of MOLF/Ei homozygosity (MOLF/MOLF), the solid line regions of C57BL/6J homozygosity (B6/B6), and the hatched segment on white background, heterozygous intervals. Congenics, including individuals with intervals of C57BL/6J homozygosity and heterozygosity (B6/B6 or heterozygous), are indicated by hatched segments on black background. Unresolved intervals at the boundaries of congenic fragments, where the genotypes have not been fixed or remain undetermined, are indicated by shaded boxes. All Ity2 congenic mice also carry the MOLF/Ei congenic fragment, Ity, on chromosome 1. The bold line by the chromosomes indicates the restricted interval defined by phenotyping the congenic mice. The relative susceptibility of each congenic strain is indicated at the bottom of each chromosome as compared to the B6.MOLF-Ity referent (R, more resistant; S, more susceptible). An asterisk by the R or S indicates that the survival does not differ from the B6.MOLF-Ity referent strain.