Haploinsufficiency of vascular endothelial growth factor related signaling genes is associated with tetralogy of Fallot
- Genet Med. 2019 Apr;21(4):1001-1007. doi: 10.1038/s41436-018-0260-9.
- 1. Ted Rogers Centre for Heart Research, Cardiac Genome Clinic, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 2. The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 3. Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 4. Genome Diagnostics, Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 5. Labatt Heart Centre, Division of Cardiology, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 6. Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
- 7. Division of Cardiology, Toronto Congenital Cardiac Centre for Adults at the Peter Munk Cardiac Centre, Department of Medicine, University Health Network, Toronto, Ontario, Canada.
- 8. Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
- 9. Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 10. Centre for Genetic Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.
- 11. Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
- 12. Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
- 13. Fred A. Litwin Family Centre in Genetic Medicine, University Health Network, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
- 14. Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada. [email protected].
- 15. Division of Cardiology, Toronto Congenital Cardiac Centre for Adults at the Peter Munk Cardiac Centre, Department of Medicine, University Health Network, Toronto, Ontario, Canada. [email protected].
- 16. The Dalglish Family 22q Clinic for Adults with 22q11.2 Deletion Syndrome, Department of Psychiatry, and Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada. [email protected].
- 17. Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada. [email protected].
Purpose: To determine disease-associated single-gene variants in conotruncal defects, particularly tetralogy of Fallot (TOF).
Methods: We analyzed for rare loss-of-function and deleterious variants in FLT4 (VEGFR3) and Other genes in the vascular endothelial growth factor (VEGF) pathway, as part of a genome Sequencing study involving 175 adults with TOF from a single site.
Results: We identified nine (5.1%) probands with novel FLT4 variants: seven loss-of-function, including an 8-kb deletion, and two predicted damaging. In ten Other probands we found likely disruptive variants in VEGF-related genes: KDR (VEGFR2; two stopgain and two nonsynonymous variants), VEGFA, FGD5, BCAR1, IQGAP1, FOXO1, and PRDM1. Detection of VEGF-related variants (19/175, 10.9%) was associated with an increased prevalence of absent pulmonary valve (26.3% vs. 3.4%, p < 0.0001) and right aortic arch (52.6% vs. 29.1%, p = 0.029). Extracardiac anomalies were rare. In an attempt to replicate findings, we identified three loss-of-function or damaging variants in FLT4, KDR, and IQGAP1 in ten independent families with TOF.
Conclusion: Loss-of-function variants in FLT4 and KDR contribute substantially to the genetic basis of TOF. The findings support dysregulated VEGF signaling as a novel mechanism contributing to the pathogenesis of TOF.