This allele harbors a frameshifting C duplication homologous to a reported case of human incontinentia pigmenti ("XL344-04", NM_001099857.3:c.1167dup). The mouse model reproduces the associated truncating mutation and adds, 5' in-frame, an EGFP open-reading frame. Expression of EGFP has been confirmed in embryonic fibroblasts. (J:94077)