CYP1B1 copy number variation is not a major contributor to primary congenital glaucoma

<p><strong>Purpose:</strong> To evaluate the prevalence and the diagnostic utility of testing for <i>CYP1B1</i> copy number variation (CNV) in primary congenital glaucoma (PCG) cases unexplained by CYP1B1 point mutations in The Australian and New Zealand Registry of Advanced Glaucoma.</p> <p><strong>Methods:</strong> In total, 50 PCG cases either heterozygous for disease-causing variants or with no <i>CYP1B1</i> sequence variants were included in the study. <i>CYP1B1</i> CNV was analyzed by Multiplex Ligation-dependent Probe Amplification (MLPA).</p> <p><strong>Results:</strong> No deletions or duplications were found in any of the cases.</p> <p><strong>Conclusion:</strong> This is the first study to report on <i>CYP1B1</i> CNV in PCG cases. Our findings show that this mechanism is not a major contributor to the phenotype and is of limited diagnostic utility.</p>