Ophthalmologic Findings in an Induced Model of Holoprosencephaly in Zebrafish

Holoprosencephaly (HPE) is the most frequent developmental disorder of the forebrain. In this condition, the separation of the early precursor domains is hampered. A spectrum of clinical manifestations can be observed, for example, severe forms like alobar HPE and less severe forms like lobar HPE. Ophthalmologic findings that accompany HPE also occur as a spectrum that ranges from ocular hypotelorism and synophthalmia to cyclopia and anophthalmia. In this brief analysis, we made use of a recently established zebrafish model of HPE. This model is based on experimental BMP ligand induction that resulted in anophthalmia. We attenuated the induction protocol to investigate whether the ophthalmologic phenotype can also be attenuated. We found a spectrum of ocular phenotypes: ocular hypotelorism, cases of synophthalmia, and cyclopia.