• defects in the adhesion of the surface ectoderm and corneal stroma

• have no true eyelids and the closed-eye appearance results from the presence of a pseudoblepharon that can be either unilateral or bilateral

• seen occasionally

• exhibit renal abnormalities

• about 20% of adults show unilateral renal agenesis

• epidermis separates from the dermis below the level of the lamina densa creating blebs/blisters during embryonic development

• Background Sensitivity: blebbing phenotype is 100% penetrant on a C57BL/6J background but is only about 70% penetrant on a mixed C57BL/6J and C3H/NeJ background

• from E13.5, develop blebs located predominantly around the eyes and the sides of the head

• upper midface is raised along the proximal aspect of the metopic suture and is wider at the level of the coronal suture

• abnormalities include medial depression along the internasal suture and/or marked curvature of the nasal bones

• most mutants exhibit abnormal maxillary-premaxillary suture morphology

• mutants exhibit advanced fusion of the posterior frontal suture compared to wild-type mice

• 7 of 16 mutants exhibit varying degrees of midfacial asymmetry and/or midface hypoplasia

• 7 of 16 mutants exhibit varying degrees of midfacial asymmetry and/or midface hypoplasia

• most mutants exhibit abnormal maxillary-premaxillary suture morphology

• mutants exhibit advanced fusion of the posterior frontal suture compared to wild-type mice

• mutants exhibit anterofrontal cranial deformation similar to metopic craniosynostosis and trigonocephaly

• mutants exhibit advanced fusion of the posterior frontal suture compared to wild-type mice, with fusion seen at postnatal day 28 compared to day 45 in controls

• 42% of heterozygotes exhibit variable sutural abnormalities, including complete fusion, sutural asymmetry and advanced endocranial suture fusion

• 2 of 21 mutants exhibit varying degrees of midfacial asymmetry and/or midface hypoplasia

• 2 of 21 mutants exhibit varying degrees of midfacial asymmetry and/or midface hypoplasia

• 42% of heterozygotes exhibit variable sutural abnormalities, including complete fusion, sutural asymmetry and advanced endocranial suture fusion

• mutants exhibit anterofrontal cranial deformation similar to metopic craniosynostosis and trigonocephaly, although less severe than seen in homozygotes