Mouse Genome Informatics
ht
    Kittm4.1Bsm/Kit+
involves: 129S1/Sv * C57BL/6J * FVB/N
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
       

Alopecia and 'red paw' in Kittm4.1Bsm/Kit+ mice

mortality/aging
• median survival is 14 months
• however, survival is improved compared to in Kittm5.1Bsm heterozygotes

hematopoietic system
• smaller in diameter than wild-type cells
• microcytic erythrocytosis reminiscent of myeloproliferative neoplasms
• between 3 and 8 weeks of age
• compared with Kittm5.1Bsm heterozygotes; without an increase in platelet count
• increased burst-forming unit erythroid (BFU-E) and erythroid (CFU-E) colonies and in the bone marrow and spleen
• more pronounced mast cell hyperplasia in the skin compared to in Kittm5.1Bsm heterozygotes
• half of male mice exhibit accumulation of mast cells around Leydig cells unlike in wild-type mice
• without an increase in platelet count
• 1.5-fold without gross alterations in splenic architecture

digestive/alimentary system
• more pronounced in the stomach and colon than in Kittm5.1Bsm heterozygotes
• reduced cecum length compared to in Kittm5.1Bsm heterozygotes

tumorigenesis
• smaller tumors than in Kittm5.1Bsm heterozygotes
• mice develop cecal tumors that are smaller than in Kittm5.1Bsm

integument
• intermittent partial alopecia between P15 and P40 associated with increased mast cells
• reddening of the paws from P40 onward

homeostasis/metabolism
• mice exhibit resistance to imatinib and dasatinib in vivo compared with Kittm5.1Bsm heterozygotes
• however, sunitinib and sorafenib overcomes resistance

immune system
• more pronounced mast cell hyperplasia in the skin compared to in Kittm5.1Bsm heterozygotes
• half of male mice exhibit accumulation of mast cells around Leydig cells unlike in wild-type mice
• 1.5-fold without gross alterations in splenic architecture

Mouse Models of Human Disease
OMIM IDRef(s)
Gastrointestinal Stromal Tumor; GIST 606764 J:188434