Related Experiment Video
Updated: Feb 21, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
Genomic Organization of TBK1 Copy Number Variations in Glaucoma Patients
Adam P DeLuca1,2, Wallace L M Alward1,2, Jeffrey Liebmann3
1Department of Ophthalmology and Visual Sciences, Carver College of Medicine.
Background:
Approximately 1% of normal tension glaucoma (NTG) cases are caused by TANK-binding kinase 1 (TBK1) gene duplications and triplications. However, the precise borders and orientation of these TBK1 gene copy number variations (CNVs) on chromosome 12 are unknown.
Methods:
We determined the exact borders of TBK1 CNVs and the orientation of duplicated or triplicated DNA segments in 5 NTG patients with different TBK1 mutations using whole-genome sequencing.
Results:
Tandemly duplicated chromosome segments spanning the TBK1 gene were detected in 4 NTG patients, each with unique borders. Four of 5 CNVs had borders located within interspersed repetitive DNA sequences (Alu and long interspersed nuclear element-L1 elements), suggesting that mismatched homologous recombinations likely generated these CNVs. A fifth NTG patient had a complex rearrangement including triplication of a chromosome segment spanning the TBK1 gene.
Conclusions:
No specific mutation hotspots for TBK1 CNVs were detected, however, interspersed repetitive sequences (ie, Alu elements) were identified at the borders of TBK1 CNVs, which suggest that mismatch of these elements during meiosis may be the mechanism that generated TBK1 gene dosage mutations.
More Related Videos
Related Concept Videos
Comparing Copy Number Variations and SNPs
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
Genetic Lingo
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Gene Duplication and Divergence
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are...
Glaucoma: Overview

