About   Help   FAQ
Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID 		Top6blem2Qsh
endonuclease-mediated mutation 2, Qinghua Shi
MGI:8323116
Summary 1 genotype
Jump to Allelic Composition Genetic Background Genotype ID
hm1
 		Top6blem2Qsh/Top6blem2Qsh involves: C57BL/6 * DBA/2J MGI:8355292


Genotype
MGI:8355292
hm1
Allelic
Composition		 Top6blem2Qsh/Top6blem2Qsh
Genetic
Background		 involves: C57BL/6 * DBA/2J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Top6blem2Qsh mutation (0 available); any Top6bl mutation (23 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
reproductive system
abnormal spermatocyte morphology ( J:383089 )
• in spread zygotene spermatocytes, the average number of REDIC1 (regulator of DNA class I crossover intermediates 1) foci on the chromosome axis per cell is significantly lower than in wild-type cells
abnormal male meiosis ( J:383089 )
• male mice do not form meiotic programmed DNA double-strand breaks (DSBs)

cellular
abnormal spermatocyte morphology ( J:383089 )
• in spread zygotene spermatocytes, the average number of REDIC1 (regulator of DNA class I crossover intermediates 1) foci on the chromosome axis per cell is significantly lower than in wild-type cells
abnormal male meiosis ( J:383089 )
• male mice do not form meiotic programmed DNA double-strand breaks (DSBs)




Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
Citing These Resources
Funding Information
Warranty Disclaimer, Privacy Notice, Licensing, & Copyright
Send questions and comments to User Support. 		last database update
06/09/2026
MGI 6.24 		The Jackson Laboratory