@article{10902/38807,
year = {2025},
url = {https://hdl.handle.net/10902/38807},
abstract = {Background: Hypertrophic cardiomyopathy (HCM) is a genetically heterogeneous disorder linked primarily to rare variants in sarcomeric genes, although recently certain nonsarcomeric genes have emerged as important contributors. Nonmendelian genetic variants with reproducible moderate-effect sizes and low penetrance, intermediate-effect variants (IEVs), can play a crucial role in modulating disease expression. Understanding the clinical impact of IEVs is crucial to unravel the complex genetic architecture of HCM.
Methods: We conducted an ancestry-based enrichment analysis of 14 validated HCM genes, including the 9 core sarcomeric and 5 nonsarcomeric genes (ALPK3, CSRP3, FHOD3, FLNC, and TRIM63). Enrichment of intermediate frequency missense variants was evaluated in 10 981 patients with HCM, 4030 internal controls of European-ancestry, and 590 000 external controls from gnomAD non-Finnish Europeans. The population-attributable fraction was calculated to assess contribution of IEVs to HCM. Age-related disease penetrance, phenotypic severity (left ventricular maximum wall thickness), and major adverse cardiac events were analyzed in 11 991 HCM cases of the whole cohort according to 5 genetic groups: genotype negative, isolated IEV, monogenic, monogenic+IEV, and double monogenic.
Results: Fourteen IEVs in 8 genes were identified in 731 individuals (6.1% of the cohort), of whom 570 patients (4.8%) had IEVs in isolation: 198 (34.7%) in sarcomeric genes and 372 (65.3%) in nonsarcomeric genes. The contribution of IEVs to HCM genetics according to population-attributable fraction was estimated to be 4.9% (95% CI, 3.2-6.7). A significant gradient in penetrance, phenotypic severity, and major adverse cardiac events was observed across genetic groups. Compared with genotype-negative patients, IEV carriers displayed a younger median age at diagnosis (59 years of age [95% CI, 46-69] versus 61 years [95% CI, 49-70]; P=0.0073) and a higher mean left ventricular maximum wall thickness (18.1±3.7 versus 19.0±4.3; P=0.0043). IEVs also modified disease expression in individuals with monogenic variants, causing a more aggressive phenotype than in individuals from the monogenic-only group with HCM onset at younger age and a higher left ventricular maximum wall thickness (all P<0.0001), with major adverse cardiac event-free survival being significantly lower (93.3% versus 69.3% at 70 years of age; P<0.0001).
Conclusions: IEVs are present in 6.1% of HCM cases and account for 4.8% of HCM genetic burden. IEVs also influence disease severity and outcomes, particularly when combined with monogenic disease-causing variants. Evaluation of IEVs should be considered when HCM genetic testing is performed.},
organization = {This project was funded by Bristol-Myers Squibb. Drs Bezzina and García-Pavía
are supported by the Pathfinder Cardiogenomics program of the European Innovation Council of the European Union (DCM-NEXT project).},
publisher = {American Heart Association},
publisher = {Circulation, 2025, 152(15), 1060-1075},
title = {Redefining the genetic architecture of hypertrophic cardiomyopathy: role of intermediate-effect variants},
author = {García Hernandez, Soledad and De la Higuera Romero, Luis and Fernandez, Adrian and Luisa Peña Peña, Maria and Mora Ayestaran, Nerea and Basurte Elorz, María Teresa and Larrañaga Moreira, Jose María and Cárdenas Reyes, Ivonne and Villacorta, Eduardo and Valverde Gómez, Maria and Baustista-Paves, Alicia and Veira Villanueva, Elena and Ortiz Genga, Martín and Lipov, Alex and Brogger, Noel and Sabater Molina, María and Moreno Escobar, Eduardo and Ruiz Guerrero, Luis Javier and Syrris, Petros and Piqueras Flores, Jesús},
}