Pediatric hypertrophic cardiomyopathy caused by a novel TNNI3 variant

Natsuko Inagaki; Tomoya Okano; Masatake Kobayashi; Masatsune Fujii; Yoshinao Yazaki; Yasuyoshi Takei; Hisanori Kosuge; Shinji Suzuki; Takeharu Hayashi; Masahiko Kuroda; Kazuhiro Satomi

doi:10.1038/s41439-024-00272-1

Pediatric hypertrophic cardiomyopathy caused by a novel TNNI3 variant

Hum Genome Var. 2024 Mar 29;11(1):14. doi: 10.1038/s41439-024-00272-1.

Authors

Affiliations

¹ Department of Cardiology, Tokyo Medical University, Tokyo, Japan. abenatsu@wb3.so-net.ne.jp.
² Department of Clinical Genetics Center, Tokyo Medical University, Tokyo, Japan. abenatsu@wb3.so-net.ne.jp.
³ Department of Cardiology, Tokyo Medical University, Tokyo, Japan.
⁴ Department of Pediatrics and Adolescent Medicine, Tokyo Medical University, Tokyo, Japan.
⁵ Department of Physiology, Tokai University School of Medicine, Isehara, Japan.
⁶ Department of Molecular Pathology, Tokyo Medical University, Tokyo, Japan.

Abstract

TNNI3 is a gene that causes hypertrophic cardiomyopathy (HCM). A 14-year-old girl who was diagnosed with nonobstructive HCM presented with cardiopulmonary arrest due to ventricular fibrillation. Genetic testing revealed a novel de novo heterozygous missense variant in TNNI3, NM_000363.5:c.583A>T (p.Ile195Phe), which was determined to be the pathogenic variant. The patient exhibited progressive myocardial fibrosis, left ventricular remodeling, and life-threatening arrhythmias. Genetic testing within families is useful for risk stratification in pediatric HCM patients.