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Updated: Mar 22, 2026

Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model
Published on: August 8, 2022
A deleterious MYH11 mutation causing familial thoracic aortic dissection.
Norifumi Takeda1, Hiroyuki Morita2, Daishi Fujita1
1Department of Cardiovascular Medicine, The University of Tokyo Hospital , Tokyo, Japan.
The myosin heavy chain 11 (MYH11) L1264P mutation, not R1275L, causes thoracic aortic aneurysms and dissections (TAAD). This finding clarifies the genetic basis of TAAD, excluding patent ductus arteriosus (PDA) in this specific familial case.
Area of Science:
- Genetics
- Cardiovascular Medicine
- Molecular Biology
Background:
- Mutations in the MYH11 gene are linked to thoracic aortic aneurysms and/or dissections (TAAD).
- Previous reports suggested that co-occurring L1264P and R1275L mutations on the same MYH11 allele cause TAAD with patent ductus arteriosus (PDA).
- The specific contribution of each mutation to TAAD/PDA pathogenesis remained unclear.
Purpose of the Study:
- To investigate the role of MYH11 mutations in the pathogenesis of TAAD.
- To differentiate the pathogenic effects of L1264P and R1275L mutations in MYH11.
- To report the first familial case of TAAD associated with a single MYH11 L1264P mutation.
Main Methods:
- Genetic sequencing of the MYH11 gene in a familial case.
- Clinical evaluation of affected individuals for TAAD and PDA.
- Comparison of mutation presence with disease phenotype.
Main Results:
- Identified a familial case of TAAD solely associated with the MYH11 L1264P mutation.
- Observed no co-occurrence of PDA in individuals with the L1264P mutation.
- The R1275L mutation was not found to be causative for TAAD in this cohort.
Conclusions:
- The MYH11 L1264P mutation is responsible for TAAD.
- The MYH11 R1275L mutation does not appear to contribute to TAAD formation.
- PDA is not an obligatory complication of MYH11-related TAAD.
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