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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID 		Dclre1ctm1Fwa
targeted mutation 1, Frederick W Alt
MGI:2667614
Summary 2 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
 		Dclre1ctm1Fwa/Dclre1ctm1Fwa involves: 129S6/SvEvTac MGI:3843212
hm2
 		Dclre1ctm1Fwa/Dclre1ctm1Fwa involves: 129S6/SvEvTac * C57BL/6 MGI:2667618


Genotype
MGI:3843212
hm1
Allelic
Composition		 Dclre1ctm1Fwa/Dclre1ctm1Fwa
Genetic
Background		 involves: 129S6/SvEvTac
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Dclre1ctm1Fwa mutation (1 available); any Dclre1c mutation (30 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
immune system
decreased thymocyte number ( J:147864 )
• thymocyte number is reduced to less than 2% of control mice
arrested B cell differentiation ( J:147864 )
• B cell development is blocked at the pro-B cell stage
abnormal T cell receptor beta chain V(D)J recombination ( J:147864 )
• the D-J and D-Jbeta1 coding joints exhibit large deletions, with >400 nt deleted from some coding flanks
• in addition, several unusually long P-nucleotide additions occur
• 24% of T cells contain N nucleotide insertions at the coding joints of greater than 5 basepairs
decreased double-positive T cell number ( J:147864 )
• there are 10-fold less double-positive thymocytes than in controls
absent B cells ( J:147864 )
• B cells are absent in the bone marrow and periphery
decreased CD4-positive, alpha-beta T cell number ( J:147864 )
• CD4+ T cells are virtually absent
decreased CD8-positive, alpha-beta T cell number ( J:147864 )
• CD8+ T cells are virtually absent
spleen hypoplasia ( J:147864 )
• spleen cellularity is 20-25% of controls

cellular
increased cellular sensitivity to gamma-irradiation ( J:147864 )
• mouse embryonic fibroblasts (MEFs) are extremely sensitive to gamma irradiation with less survival occurring compared to wild-type controls
induced chromosome breakage ( J:147864 )
• MEFs have increased levels of chromosomal aberrations 24 h after 200 rads similar to levels observed in MEFs

hematopoietic system
decreased thymocyte number ( J:147864 )
• thymocyte number is reduced to less than 2% of control mice
arrested B cell differentiation ( J:147864 )
• B cell development is blocked at the pro-B cell stage
abnormal T cell receptor beta chain V(D)J recombination ( J:147864 )
• the D-J and D-Jbeta1 coding joints exhibit large deletions, with >400 nt deleted from some coding flanks
• in addition, several unusually long P-nucleotide additions occur
• 24% of T cells contain N nucleotide insertions at the coding joints of greater than 5 basepairs
decreased double-positive T cell number ( J:147864 )
• there are 10-fold less double-positive thymocytes than in controls
absent B cells ( J:147864 )
• B cells are absent in the bone marrow and periphery
decreased CD4-positive, alpha-beta T cell number ( J:147864 )
• CD4+ T cells are virtually absent
decreased CD8-positive, alpha-beta T cell number ( J:147864 )
• CD8+ T cells are virtually absent
spleen hypoplasia ( J:147864 )
• spleen cellularity is 20-25% of controls

endocrine/exocrine glands
decreased thymocyte number ( J:147864 )
• thymocyte number is reduced to less than 2% of control mice




Genotype
MGI:2667618
hm2
Allelic
Composition		 Dclre1ctm1Fwa/Dclre1ctm1Fwa
Genetic
Background		 involves: 129S6/SvEvTac * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Dclre1ctm1Fwa mutation (1 available); any Dclre1c mutation (30 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
cellular
increased cellular sensitivity to ionizing radiation ( J:80995 )
• mouse embryonic fibroblasts (MEFs) exhibit increased ionizing radiation sensitivity but normal growth
chromosomal instability ( J:80995 )
• spontaneous chromosomal instability is increased in MEFs

hematopoietic system
decreased thymocyte number ( J:80995 )
• total thymocyte numbers are reduced 50-fold
absent immature B cells ( J:80995 )
• B220+IgM+ immature B cell population is absent
arrested B cell differentiation ( J:80995 )
• B cell development is blocked at the B220+CD43+ progenitor stage when Ig rearrangements first occur
arrested T cell differentiation ( J:80995 )
• T cell development is partially blocked at the CD4-CD8- double negative progenitor stage when Tcr rearrangements first occur

immune system
decreased thymocyte number ( J:80995 )
• total thymocyte numbers are reduced 50-fold
absent immature B cells ( J:80995 )
• B220+IgM+ immature B cell population is absent
arrested B cell differentiation ( J:80995 )
• B cell development is blocked at the B220+CD43+ progenitor stage when Ig rearrangements first occur
arrested T cell differentiation ( J:80995 )
• T cell development is partially blocked at the CD4-CD8- double negative progenitor stage when Tcr rearrangements first occur

endocrine/exocrine glands
decreased thymocyte number ( J:80995 )
• total thymocyte numbers are reduced 50-fold




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Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
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Send questions and comments to User Support. 		last database update
04/23/2024
MGI 6.23 		The Jackson Laboratory