Experiment
Advanced intercross lines (AILs) derived from A/JOlaHsd and C57BL/6JOlaHsd at the F11 generation were used to map QTLs associated with malaria resistance. AIL animals were challenged at 12- to 14-weeks of age by intraperitoneal injection with 3 x 10(6) Plasmodium chabaudi parasitized red blood cells. Parental strain A/JOlaHsd is susceptible to infection by P.chabaudi whereas parental strain C57BL/6JOlaHds is resistant. Mouse chromosomes showing previous linkage to malaria resistance (chrs. 5, 8, and 17) were screened at an average resolution of 1 cM - 3 cM in this study.
Two novel and tightly linked QTLs, Char5 and Char6, were identified at 77 cM and 80 cM on mouse Chromosome 5. Char5 maps near D5Mit165 and D5Mit168; Char6 maps near D5Mit168 and D5Mit99. Both loci appear to have an effect during the highest parasitemia days. Potential candidate genes mapping to the Char5/Char6 region include Ache, Epo, Hspb1, Act1, and Ncf1. Previously identified QTL Cora1 also maps to this region (73 cM).
Previously identified QTL Char2 was confirmed in this study.
1.21.2016 Curators Note: Because Char2 was originally mapped using an (C3H/He x C57BL/6)F2
cross in J:44414, which differs from the mapping population used here, we consider the current study a separate mapping experiment and have named this QTL Char12, P. chabaudi malaria resistance QTL 12 .
Char12 mapped to 35 cM on mouse Chromosome 8 between D8Mit73 and D8Mit195. The confidence interval of this locus was narrowed to a 13-16 cM interval. Char12 appears to have an effect during the early stage of infection. Potential candidate genes mapping near Char12 include Gypa, Ea1, Cspg3, Il12rb1, and Il15.
Previously identified QTL Char3 at 24 cM on mouse Chromosome 17 was resolved to 2 separate loci.
1.21.2016 Curator Note: Because Char3 was originally mapped in J:72455 using a population of (C3H/He x C57BL/6)F2 mice, which differ from the population used here, we consider the current study a separate mapping experiment and have renamed the QTL identified here as Char3 to Char13. The current study is the original map experiment for Char7 so that nomenclature will be retained.
The second locus, named Char7, peaked at 34 cM near D17Mit87 and D17Mit119. Both QTLs appear to have an effect during the early stages of challenge. Char13 maps close to the H2 locus. Potential candidate genes near Char13 include Lta, Ltb, Tnf, Tnfsf7, Tnfsf14, Ifi15, and Thy2. Potential candidate genes mapping near Char7 include C6, Ir5,and D17Wsu104e (formerly Il25).