Mapping Data

Experiment

• Experiment
  TEXT-Congenic
• Chromosome
  4
• Reference
  J:140749 Avagyan S, et al., A quantitative trait locus on chromosome 4 affects cycling of hematopoietic stem and progenitor cells through regulation of TGF-beta2 responsiveness. J Immunol. 2008 Nov 1;181(9):5904-11
• ID
  MGI:3821866

Genes

Gene	Assay Type
Tb2r1	visible phenotype
D4Mit37	PCR amplified length variant

Notes

• Experiment
  Previously identified QTL Lskcn (73 cM) on distal mouse Chromosome 4 was confirmed in this study using congenic line analysis. Authors officially designate this locus Tb2r1 (TGF-beta2 responsiveness 1). The telomeric portion of chromosome 4 spanning 20 cM derived from DBA/2J donor DNA was backcrossed onto a C57BL/6J genetic background to generate B6.D2-(D4Mit37-tel) congenic animals carrying the Tb2r1 locus. The absolute number of Lin(-)Sca1(++)c-kit(+) cells (LSK phenotype) is 2-fold higher in C57BL/6J than in DBA/2J, and LSK cell proliferation is more responsive to stimulation with TGF-beta2 in C57BL/6J mice than in DBA/2J mice.
  
  LSK cells from B6.D2-(D4Mit37-tel) congenic animals displayed blunted proliferative responsiveness after stimulation with low concentrations of TGF-beta2 compared to background strain C57BL/6J. The frequency of LSK cells and cycling of hemotopoietic stem and progenitor cell (HSPC) compartment in B6.D2-(D4Mit37-tel) congenic animals was also decreased compared to C57BL/6J. Some of the phenotypes observed in B6.D2-(D4Mit37-tel) congenic animals are similar to that of Tgfb2^tm1Doe/Tgfb2⁺ mice.
  
  Authors speculate a second QTL may be present in the 20 cM congenic region of B6.D2-(D4Mit37-tel) animals controlling repopulation capacity of hematopoietic stem cells after serial transplantation.
  
  Over 170 genes are located in the 20 cM congenic interval. Potential candidate genes for Tb2r1 include Ski (78.9 cM), Prdm16, Tnfrsf9 (75.5 cM) and Tnfrsf14.