Novel and rare variants in the ADAMTS18 are likely causes of the microcornea, myopic chorioretinal atrophy, and telecanthus in a Vietnamese patient

Abstract: The congenital ocular anomaly with microcornea is a rare and poorly understood disorder in Vietnam. This report describes the clinical characteristics of a female baby with complex ocular anomalies and genetic findings. The patient exhibited bilateral microcornea, exotropia, telecanthus, and falciform fold in oculus dexter and choroidal degeneration in oculus sinister. Ophthalmic examination revealed proliferative retinopathy without retinal detachment in both eyes and strabismus. Genetic examination identified two heterozygous missense variants in the A disintegrin and metalloproteinase with thrombospondin motifs 18 ( ADAMTS18 ) gene of the patient: a novel variant c.1148A>T; p.(H383 L) inherited from her mother and a rare variant c.2065G>A; p.(E689K) from her father. Both variants changed the conservative amino acids and were predicted to damage the protein functions. Expanding the genetic variant spectrum related to congenital ocular anomalies, this report also stresses the significance of genetic screening for the early diagnosis of complex syndromes in future.