Glaucoma is a clinically and genetically complex disease that is the leading cause of irreversible blindness worldwide. The disease exhibits both complex and Mendelian inheritance with complex disease more common in adult populations and Mendelian forms more common in children and young adults. While recent genome- wide association studies (GWAS) have identified >100 risk loci for adult-onset disease, only 10 genes are known to cause early-onset glaucoma (EOG, glaucoma developing before age 40), and few studies have targeted this severely affected population. The current set of EOG genes can explain only 20% of cases, leaving most affected individuals without a molecular diagnosis. Treatment options for EOG cases are limited and these patients are most likely to become blind during their lifetimes. The overall goal of this proposal is to discover novel EOG causal genes that will provide opportunities for gene-based screening and diagnostic tests, allowing for improved risk prediction and genetic counseling, as well as new, and potentially curative, therapeutic targets. The current lack of EOG genes creates a pressing need to study genetic variation across the full length of the genome in these severely affected glaucoma cases. Using whole genome sequencing (WGS) we will create a comprehensive set of variants for genomic analyses for two large collections of clinically well-characterized early-onset glaucoma probands and families through a collaboration between the USA and Australia. We will accomplish the following specific aims: 1) Comprehensively identify all genetic variants in at least 1000 EOG probands and selected family members using high quality WGS data and robust variant calling and annotation pipelines; 2) Discover novel highly penetrant genetic variants in novel causative genes in EOG patients and families; and 3) Examine oliogogenic inheritance and assess relationships of EOG genes with adult-onset disease (primary open angle glaucoma).
Individuals who develop glaucoma before age 40 (early-onset glaucoma) have few treatment options and are most likely to become blind during their lifetimes. Only ten genes are known to cause this condition and these only account for 20% of cases leaving most patients without a molecular diagnosis. The overall goal of this proposal is to discover novel early-onset glaucoma causal genes that will provide opportunities for gene-based screening and diagnostic tests, allowing for improved risk prediction and genetic counseling, as well as new, and potentially curative, therapeutic targets.
