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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID 		Shld1em1Nus
endonuclease-mediated mutation 1, Andre Nussenzweig
MGI:6719506
Summary 2 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
 		Shld1em1Nus/Shld1em1Nus involves: C57BL/6NCrl MGI:6739935
cx2
 		Brca1tm2.1Cxd/Brca1tm2.1Cxd
Shld1em1Nus/Shld1em1Nus 		involves: 129S6/SvEvTac * C57BL/6NCrl MGI:6739936


Genotype
MGI:6739935
hm1
Allelic
Composition		 Shld1em1Nus/Shld1em1Nus
Genetic
Background		 involves: C57BL/6NCrl
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Shld1em1Nus mutation (0 available); any Shld1 mutation (77 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
immune system
abnormal class switch recombination ( J:307190 )
• mice show defects in IgG1 class switch recombination

hematopoietic system
abnormal class switch recombination ( J:307190 )
• mice show defects in IgG1 class switch recombination

mortality/aging
mortality/aging ( J:307190 )
N
• mice are viable and do not show any overt phenotypes




Genotype
MGI:6739936
cx2
Allelic
Composition		 Brca1tm2.1Cxd/Brca1tm2.1Cxd
Shld1em1Nus/Shld1em1Nus
Genetic
Background		 involves: 129S6/SvEvTac * C57BL/6NCrl
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm2.1Cxd mutation (0 available); any Brca1 mutation (113 available)
Shld1em1Nus mutation (0 available); any Shld1 mutation (77 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
immune system
abnormal class switch recombination ( J:307190 )
• mice show defects in IgG1 class switch recombination

hematopoietic system
abnormal class switch recombination ( J:307190 )
• mice show defects in IgG1 class switch recombination

cellular
chromosomal instability ( J:307190 )
• PARPi-induced genome instability is lower in primary B cells compared to that seen in homozygous Brca1 mutant cells but still increased compared to in wild-type cells

mortality/aging
mortality/aging ( J:307190 )
N
• the expected Mendelian ratio of mice are obtained, indicating rescue of the embryonic lethality of homozygous Brca1 mutants




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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
09/30/2025
MGI 6.24 		The Jackson Laboratory