Summary of all IKMC allele types

The wild-type is represented as a transcript with three exons. The ‘floxed’ exon (the exon that will be deleted for the null allele) is exon number 2.

EUCOMM, KOMP-CSD Targeted mutations

EUCOMM and KOMP-CSD make both promoter-driven and promoterless alleles, which are termed ‘knockout first’ or ‘pre-conditional’. They are initially null, but can be made into conditional alleles by application of Flp recombinase - this will excise the cassette between the FRT sites. The null can be recovered by application of Cre recombinase.

EUCOMM and KOMP-CSD also inadvertently produce targeted promoter-driven and promoterless alleles which are null and non-conditional. These alleles have lost the loxP site three-prime of the floxed exon (exon 2), and so cannot be converted to conditional alleles.

KOMP-CSD also produce targeted deletions

KOMP Regeneron targeted mutations

Regeneron make lacZ-tagged, promoter-driven deletions

NorCOMM targeted mutations

EUCOMM gene-traps

TIGM gene-traps