The identification and stereochemistry analysis of a novel mutation p.(D367Tfs*61) in the CYP1B1 gene: A case report

Abstract

Purpose: To investigate the presence of a probable genetic defect(s) that may cause primary congenital glaucoma (PCG) in a seven-year-old female patient. Methods: A seven-year-old female patient and her family received genetic counseling and underwent full clinical examinations by an expert ophthalmologist. The patient's genomic DNA was subjected to the targeted gene capture and next-generation sequencing (NGS) along with Sanger sequencing method. The 3D structure prediction and stereochemistry analysis were performed for both mutant and wild-type forms of the CYP1B1 protein. Results: The clinical examinations indicated that the diagnosis of PCG was correctly made. We identified a novel homozygous deletion in which a "C" nucleotide was deleted from the final exon of the Cytochrome P450 Family 1 Subfamily B Member 1 (CYP1B1) gene. The 3D molecular modeling of the CYP1B1 protein predicted significant structural changes could occur in this protein as a result of the mutation mentioned earlier. The stereochemistry analysis revealed mutant features of the protein, as well as significant misfolding and possible malfunctions in the mutant form of the CYP1B1 protein. Conclusions: This mutation might cause a frameshift in the translation process, leading to the malfunction of the CYP1B1 protein and development of glaucoma. This newly-identified mutation could be regarded as potential deletion mutation in genetic counseling and molecular examination for the detection of PCG disease in Iran.