According to the allele image posted by EUCOMMTOOLS in the international knockout mouse consortium site (https://www.mousephenotype.org/imits/targ_rep), exons 4 and 5 are flanked by loxP sites and a cre/ERT2-EGRP cassette preceded by a single FRT site and followed by a Rox flanked puromycin selection cassette was inserted into the intron between exons 3 and 4. (J:155845)
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cx: complex: > 1 genome feature ot: other: hemizygous, indeterminate,... (F): Female
(M): Male
N: normal phenotype
(#): related diseases count