Cap Myopathy

Last update 01 Nov 2024

Basic Info

Synonyms

Cap Disease, Cap Myopathy, Cap disease

+ [5]

Introduction

Cap myopathy is a very rare congenital myopathy presenting a weakness of facial and respiratory muscles associated with craniofacial and thoracic deformities, as well as weakness of limb proximal and distal muscles. Onset is at birth or in childhood, weakness progression is slow but may lead to a severe and even fatal prognosis.

100 Clinical Results associated with Cap Myopathy

100 Translational Medicine associated with Cap Myopathy

0 Patents (Medical) associated with Cap Myopathy

Literatures (Medical) associated with Cap Myopathy

22 Jun 2022·JCI Insight

A pathogenic mechanism associated with myopathies and structural birth defects involves TPM2-directed myogenesis

Article

Author: Ou, Tiffany ; Huang, Gary ; Greenberg, Michael J ; Johnson, Aaron N ; Gurnett, Christina A ; McAdow, Jennifer ; Yang, Shuo ; Dobbs, Matthew B

Nemaline myopathy (NM) is the most common congenital myopathy, characterized by extreme weakness of the respiratory, limb, and facial muscles. Pathogenic variants in Tropomyosin 2 (TPM2), which encodes a skeletal muscle-specific actin binding protein essential for sarcomere function, cause a spectrum of musculoskeletal disorders that include NM as well as cap myopathy, congenital fiber type disproportion, and distal arthrogryposis (DA). The in vivo pathomechanisms underlying TPM2-related disorders are unknown, so we expressed a series of dominant, pathogenic TPM2 variants in Drosophila embryos and found 4 variants significantly affected muscle development and muscle function. Transient overexpression of the 4 variants also disrupted the morphogenesis of mouse myotubes in vitro and negatively affected zebrafish muscle development in vivo. We used transient overexpression assays in zebrafish to characterize 2 potentially novel TPM2 variants and 1 recurring variant that we identified in patients with DA (V129A, E139K, A155T, respectively) and found these variants caused musculoskeletal defects similar to those of known pathogenic variants. The consistency of musculoskeletal phenotypes in our assays correlated with the severity of clinical phenotypes observed in our patients with DA, suggesting disrupted myogenesis is a potentially novel pathomechanism of TPM2 disorders and that our myogenic assays can predict the clinical severity of TPM2 variants.

01 Sep 2021·Genes & DiseasesQ1 · MEDICINE

The R168G heterozygous mutation of tropomyosin 3 (TPM3) was identified in three family members and has manifestations ranging from asymptotic to serve scoliosis and respiratory complications

Q1 · MEDICINE

ArticleOA

Author: Xu, Haoyue ; Luo, Cong ; Zhu, Jin ; Song, Bo ; Li, Ming ; Chen, Tao ; Liu, Xing ; Liu, Hang

According to existing reports, mutations in the slow tropomyosin gene (TPM3) may lead to congenital fiber-type disproportion (CFTD), nemaline myopathy (NM) and cap myopathy (CD). They are all congenital myopathies and are associated with clinical, pathological and genetic heterogeneity. A ten-year-old girl with scoliosis was unable to wean from mechanical ventilation after total intravenous anesthesia. The girl has scoliosis, respiratory insufficiency, motion delay and muscle weakness; her younger brother has a similar physiology but does not have scoliosis or respiratory insufficiency, and her parents are healthy. We conducted genetic testing and found a c.502C > G (p.R168G) heterozygous mutation in the family. This mutation originated from the father and was autosomal dominant. Muscle biopsy results indicated that no special structures were present, and the type I fiber ratio was not notably high compared to previous reports. Although the family members have the same mutations, their clinical manifestations are quite different.

01 May 2021·Clinical Genetics

Whole genome sequencing reveals biallelic PLA2G6 mutations in siblings with cerebellar atrophy and cap myopathy

Letter

Author: Marshall, Aren E. ; Marshall, Christian R. ; Kernohan, Kristin D. ; McMillan, Hugh J. ; Michaud, Jean ; Warman‐Chardon, Jodi ; Boycott, Kym M. ; Dyment, David A. ; Ramani, Arun K. ; Hartley, Taila ; Venkateswaran, Sunita

It was reported that two brothers was initially presented with progressive ataxia due to cerebellar atrophy.The index case developed proximal weakness prompting a muscle biopsy which revealed findings consistent with a cap myopathy.Subsequent whole genome sequencing (WGS) identified biallelic variants in PLA2G6 consistent with phospholipase A2-group VI (PLA2G6) associated neurodegeneration (PLAN).The results highlight that PLA2G6 may have a role in skeletal muscle, expanding the known phenotype and highlights the utility of WGS.A 14 yr old boy had normal early development until 4 years old when he developed ataxia and MRI brain at age 5-1/2 years revealed cerebellar atrophy.Phys. examination at 6 years of age noted: dysarthria, dysmetria, proximal muscle weakness, spasticity and heel cord contractures, lower limb hyperreflexia and extensor plantar responses, none of which had been present on his neurol. examination 18 mo earlier.WGS revealed compound heterozygous variants in PLA2G6: NM_001004426.2:c.2060G>A; p.Arg687Gln; c.-45-1701_209+2181del.Repeat MRI brain at 12-years old showed T2 weighted images (T2WI) and susceptibility weighted images (SWI) hypointensities in the basal ganglia consistent with neuronal brain iron accumulation.Brain-iron accumulation may not always be apparent on MR imaging of symptomatic patients particularly if performed early in the disease course or if susceptibility weighted imaging sequences are not included.Using DNA from lymphoblast cells derived from Case 1, real-time polymerase chain reaction (PCR) and long-range PCR were used to confirm the genomic deletion within PLA2G6.The cap myopathy seen in this patient with PLAN demonstrated less abundant cap structures with no accompanying nemaline rods and the cap structures in this patient were not seen on NADH or ATPase stains which could be attributed to the lower number of cap structures or a qual. difference with the cap structure itself.This study shows that the phenotypic spectrum of neurodegeneration with brain iron accumulation can include features overlapping with cap myopathy and highlights the benefits of WGS for obtaining a definitive diagnosis for patients with a rare disease.

Analysis

Perform a panoramic analysis of this field.

view full example data

AI Agents Built for Biopharma Breakthroughs

Accelerate discovery. Empower decisions. Transform outcomes.

Get started for free today!

Accelerate Strategic R&D decision making with Synapse, PatSnap’s AI-powered Connected Innovation Intelligence Platform Built for Life Sciences Professionals.

Start your data trial now!

Synapse data is also accessible to external entities via APIs or data packages. Empower better decisions with the latest in pharmaceutical intelligence.

Bio

Bio Sequences Search & Analysis

Chemical

Chemical Structures Search & Analysis

Cap Myopathy

Basic Info

Related

Analysis