Related Experiment Video
Updated: Jun 9, 2026
07:15
Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Long QT Syndrome Type 5 With Coexisting KCNE1 and RYR2 Variants: A Diagnostic Ambiguity
Mohammad Hossein Nikoo1, Hossein Fatemian2, Amir Hossein Hassani2
1Non-Communicable Research Center Shiraz University of Medical Sciences Shiraz Iran.
Clinical Case Reports
|June 8, 2026
Summary
Rare Type 5 Long QT syndrome (LQTS) in a teen girl caused syncope. Genetic testing revealed KCNE1 and RYR2 variants, managed with beta-blockers and ICD, preventing further events.
Area of Science:
- Cardiology
- Genetics
- Molecular Biology
Background:
- Long QT syndrome (LQTS) is a cardiac disorder increasing syncope and sudden death risk.
- Type 5 LQTS, associated with KCNE1 gene variants, is an uncommon subtype.
- Recurrent syncope in adolescents warrants investigation for underlying cardiac conditions.
Purpose of the Study:
- To report a rare case of Type 5 LQTS in a teenage female.
- To describe the diagnostic process, including ECG and genetic testing.
- To illustrate genotype-phenotype correlations and management strategies for LQTS.
Main Methods:
- Clinical presentation of recurrent syncope in a teenage female.
- Electrocardiogram (ECG) analysis revealing a prolonged QTc interval (485 ms).
- Comprehensive genetic testing identifying variants in KCNE1 and RYR2 genes.
Main Results:
- The patient presented with syncope, indicative of cardiac arrhythmia.
- Genetic analysis confirmed mutations in KCNE1 (associated with Type 5 LQTS) and RYR2.
- Treatment with beta-blockers and an implantable cardioverter-defibrillator (ICD) successfully prevented recurrent events.
Conclusions:
- This case underscores the importance of considering rare LQTS types in adolescent syncope.
- Genetic testing is crucial for accurate diagnosis and identifying specific gene variants.
- Effective management involving pharmacotherapy and device implantation can mitigate risks associated with LQTS.
Related Concept Videos
01:17Karyotyping
Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is facilitated by special staining techniques that produce a particular banding pattern on each chromosome. State-of-the-art techniques make this approach even more powerful, enabling the detection of individual genes that cause disease.A Simple Chromosome Staining Technique Provides Valuable Scientific InsightSome genetic diseases can be detected by looking at...
01:17Karyotyping
Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is facilitated by special staining techniques that produce a particular banding pattern on each chromosome. State-of-the-art techniques make this approach even more powerful, enabling the detection of individual genes that cause disease.A Simple Chromosome Staining Technique Provides Valuable Scientific InsightSome genetic diseases can be detected by looking at...
01:30Acute Coronary Syndrome III: Diagnostic Studies
Diagnosing acute coronary syndrome or ACS begins with a thorough patient history. Notable symptoms include central, crushing chest pain radiating to the left arm, neck, jaw, or back, along with shortness of breath, sweating (diaphoresis), nausea, vomiting, dizziness, and palpitations.It is crucial to note any history of cardiac illnesses and assess risk factors, including age, gender, smoking, hypertension, diabetes, hyperlipidemia, and a sedentary lifestyle.During physical examination, vital...
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
01:21Aneurysm II: Clinical Manifestations and Diagnostic Studies
Thoracic, aortic arch and abdominal aneurysms are significant vascular conditions that can present with various clinical manifestations and lead to serious complications. Understanding these manifestations and the appropriate diagnostic studies is essential for effective management and treatment.Thoracic Aortic AneurysmsThoracic aortic aneurysms often remain asymptomatic until they reach a size that impinges on adjacent structures. They typically cause deep, diffuse chest pain that radiates to...
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests
Mitral stenosis is a heart condition in which the mitral valve, which allows blood to flow from the left atrium to the left ventricle, becomes narrowed or stenotic. This narrowing hinders blood flow and leads to clinical symptoms requiring specific medical evaluations and management strategies. The following overview outlines the clinical symptoms, assessments, diagnostic findings, prevention methods, and treatments for mitral stenosis.Clinical ManifestationsDyspnea (shortness of breath): This...