This thesis aims to present some of the research we have performed on the genetics of the eye and of anterior segment dysgenesis. Our goal was to better understand the genetics of the eye development consecutive to genetic disorders. The presented studies were performed at a time when exome/genome sequencing for the purposes of molecular diagnosis was not widely performed and in which the advances in molecular analyses were not those we have today. Genetic counseling played a crucial role in assisting families, despite challenges posed by issues like incomplete penetrance and germinal mosaicism. The study of asymptomatic family members revealed previously undiagnosed mild phenotypes, further highlighting the complexity of these disorders. The identification of novel phenotypes and genotypes emphasized the ongoing need for comprehensive knowledge to better understand eye malformations.

The studies focused on various pathologies, with a significant number of families with anophthalmia/microphthalmia (A/M) being collected and studied. Other malformations, including anterior segment eye malformations (such as iris coloboma, congenital cataract, and congenital glaucoma), were also observed, often with or without associated systemic syndromes. These investigations led to the identification of new phenotypes and genotypes, contributing to the understanding of these malformations and their etiology. In conclusion, this thesis provides valuable insights into the genetics of eye development and anterior segment dysgenesis. The findings contribute to the understanding of phenotypes, genotypes, and the complex interplay of genetic and environmental factors in these disorders. The knowledge gained from these studies has the potential to enhance molecular diagnostics, refine genetic counseling, and improve medical management for affected individuals in the future.