Format

Send to

Choose Destination
Circulation. 2015 Jun 9;131(23):2051-60. doi: 10.1161/CIRCULATIONAHA.115.015397. Epub 2015 Apr 28.

Homozygous/Compound Heterozygous Triadin Mutations Associated With Autosomal-Recessive Long-QT Syndrome and Pediatric Sudden Cardiac Arrest: Elucidation of the Triadin Knockout Syndrome.

Author information

1
From Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (H.M.A., D.J.T., M.L.W., M.J.A.), Department of Medicine/Division of Cardiovascular Diseases (D.J.T., M.L.W., M.J.A.), Medical Genome Facility (B.W.E.), and Department of Pediatrics/Division of Pediatric Cardiology (M.J.A.), Mayo Clinic, Rochester, MN; and Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo College of Medicine, Rochester, MN (S.M., J.M.E.).
2
From Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (H.M.A., D.J.T., M.L.W., M.J.A.), Department of Medicine/Division of Cardiovascular Diseases (D.J.T., M.L.W., M.J.A.), Medical Genome Facility (B.W.E.), and Department of Pediatrics/Division of Pediatric Cardiology (M.J.A.), Mayo Clinic, Rochester, MN; and Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo College of Medicine, Rochester, MN (S.M., J.M.E.). ackerman.michael@mayo.edu.

Abstract

BACKGROUND:

Long-QT syndrome (LQTS) may result in syncope, seizures, or sudden cardiac arrest. Although 16 LQTS-susceptibility genes have been discovered, 20% to 25% of LQTS remains genetically elusive.

METHODS AND RESULTS:

We performed whole-exome sequencing child-parent trio analysis followed by recessive and sporadic inheritance modeling and disease-network candidate analysis gene ranking to identify a novel underlying genetic mechanism for LQTS. Subsequent mutational analysis of the candidate gene was performed with polymerase chain reaction, denaturing high-performance liquid chromatography, and DNA sequencing on a cohort of 33 additional unrelated patients with genetically elusive LQTS. After whole-exome sequencing and variant filtration, a homozygous p.D18fs*13 TRDN-encoded triadin frameshift mutation was discovered in a 10-year-old female patient with LQTS with a QTc of 500 milliseconds who experienced recurrent exertion-induced syncope/cardiac arrest beginning at 1 year of age. Subsequent mutational analysis of TRDN revealed either homozygous or compound heterozygous frameshift mutations in 4 of 33 unrelated cases of LQTS (12%). All 5 TRDN-null patients displayed extensive T-wave inversions in precordial leads V1 through V4, with either persistent or transient QT prolongation and severe disease expression of exercise-induced cardiac arrest in early childhood (≤3 years of age) and required aggressive therapy. The overall yield of TRDN mutations was significantly greater in patients ≤10 years of age (5 of 10, 50%) compared with older patients (0 of 24, 0%; P=0.0009).

CONCLUSIONS:

We identified TRDN as a novel underlying genetic basis for recessively inherited LQTS. All TRDN-null patients had strikingly similar phenotypes. Given the recurrent nature of potential lethal arrhythmias, patients fitting this phenotypic profile should undergo cardiac TRDN genetic testing.

KEYWORDS:

arrhythmias, cardiac; genetics; heart arrest; humans; long QT syndrome; pediatrics

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center