An internal ribosome entry site-YFP-2A-human HBGEF-loxP-Cre-neoR-loxP cassette was introduced in the 3 untranslated region of the gene, downstream of the stop codon. Germline transmission led to the self-excision of the loxP-Cre-NeoR-loxP cassette in male germinal cells leaving the YFP and human diptheria toxin receptor gene. (J:236069)