Genetic studies of B-lymphocyte deficiency and mastocytosis in strain A/WySnJ mice.
The A/WySnJ mouse, but not the related A/J strain, has peripheral B-lymphocyte deficiency and mastocytosis. Minimally, two quantitative trait loci (QTLs) control the B-cell deficiency in (A/WySnJ x CAST/Ei)F2 intercross mice; one of them, Bcmd-1, mapped to Chromosome (Chr) 15. Several QTLs controlled the mastocytosis in this intercross, and it was not possible to determine whether any of them co-segregated with Bcmd-1. We have now mapped a second QTL controlling the B-cell deficiency, Bcmd-2, to Chr 4. Furthermore, we narrowed the map position of Bcmd-1 to <2.0 cM. Both QTLs have been confirmed through the construction of AW. Bcmd-1(c), AW. Bcmd-2(c), and AW. Bcmd-1(c)Bcmd-2(c) recombinant congenic strains. The Bcmd-1 locus is the major regulator of B-cell homeostasis, while Bcmd-2 is the minor regulator, and their effects are additive, as shown by splenic B-cells analysis in these congenic strains. In addition, Bcmd-2 or a linked locus controls mastocytosis, while Bcmd-1 does not, as indicated by splenic mast cell analysis in the congenic strains. Thus, the major genetic controls on B-cell homeostasis and mast cell homeostasis in A/WySnJ mice are asserted by distinct genes.
Clise-Dwyer
K
K
Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA.
Amanna
I J
IJ
Duzeski
J L
JL
Nashold
F E
FE
Hayes
C E
CE
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002874:Chromosome Mapping; D006706:Homeostasis / Q000235:genetics; D007153:Immunologic Deficiency Syndromes / Q000235:genetics* / Q000276:immunology*; D008407:Mast Cells / Q000276:immunology / Q000473:pathology; D008415:Mastocytosis / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D051379:Mice; D020297:Mice, Congenic; D008805:Mice, Inbred A; D019655:Quantitative Trait, Heritable