Genome sequencing in congenital cataracts improves diagnostic yield
Alan Ma1,2,3, John R Grigg1,4,5,6, Maree Flaherty4,5
1Eye Genetics Research Unit, The Children's Hospital at Westmead, Save Sight Institute, Children's Medical Research Institute, University of Sydney, Sydney, New South Wales, Australia.
Human Mutation
|June 8, 2021
Summary
Genome sequencing significantly improves the diagnosis of congenital cataracts, a leading cause of childhood blindness. This advanced genetic testing identifies variants missed by other methods, increasing the overall diagnostic rate for affected families.
Area of Science:
- Ophthalmology
- Genetics
- Medical Diagnostics
Background:
- Congenital cataracts are a primary cause of blindness in children globally.
- Genetic diagnosis offers crucial benefits, including targeted testing and family genetic information.
Purpose of the Study:
- To evaluate the diagnostic value of genome sequencing in congenital cataract patients.
- To assess the added diagnostic yield of genome sequencing compared to previous genetic approaches.
Main Methods:
- Genome sequencing was applied to 20 probands with congenital cataracts.
- A cohort of 52 probands was analyzed, including 14 previously undiagnosed cases.
- Analysis focused on identifying variants missed by microarray, exome, or panel-based methods.
Main Results:
- Genome sequencing achieved an overall diagnostic rate of 77% (40/52) in the cohort.
- It provided additional diagnoses in 10% (5/52) of cases by detecting small copy number variants, indels in repetitive regions, and SNVs in GC-rich areas.
- Exome or genome sequencing alone would have identified variants in 67% of cases.
Conclusions:
- Genome sequencing offers a significant advantage for diagnosing congenital cataracts, especially in complex cases.
- This method enhances diagnostic yield by detecting variant types not identifiable through exome sequencing or microarrays.
- The study underscores the importance of genome sequencing for comprehensive genetic diagnosis in pediatric eye diseases.
