Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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Query: UMLS:C0029089 (
ophthalmoplegia
)
3,338
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Multiminicore disease is a recessive congenital myopathy characterized by the presence of small cores or areas lacking oxidative enzymes, in skeletal muscle fibres. From a clinical point of view, the condition is widely heterogeneous and at least four phenotypes have been identified; genetic analysis has revealed that most patients with the classical form of multiminicore characterized by rigidity of the spine, early onset and respiratory impairment harbour recessive mutations in the
SEPN1
gene, whereas the majority of patients belonging to the other categories, including patients with
ophthalmoplegia
or patients with a phenotype similar to central core disease, carry recessive mutations in the RYR1. In the present review we discuss the most recent findings on the functional effect of mutations in
SEPN1
and RYR1 and discuss how they may adversely affect muscle function and lead to the clinical phenotype.
...
PMID:Functional effects of mutations identified in patients with multiminicore disease. 1736 75
Multi-minicore Disease (MmD) is a recessively inherited neuromuscular disorder characterized by multiple cores on muscle biopsy and clinical features of a congenital myopathy. Prevalence is unknown. Marked clinical variability corresponds to genetic heterogeneity: the most instantly recognizable classic phenotype characterized by spinal rigidity, early scoliosis and respiratory impairment is due to recessive mutations in the
selenoprotein N
(
SEPN1
) gene, whereas recessive mutations in the skeletal muscle ryanodine receptor (RYR1) gene have been associated with a wider range of clinical features comprising external
ophthalmoplegia
, distal weakness and wasting or predominant hip girdle involvement resembling central core disease (CCD). In the latter forms, there may also be a histopathologic continuum with CCD due to dominant RYR1 mutations, reflecting the common genetic background. Pathogenetic mechanisms of RYR1-related MmD are currently not well understood, but likely to involve altered excitability and/or changes in calcium homeoestasis; calcium-binding motifs within the
selenoprotein N
protein also suggest a possible role in calcium handling. The diagnosis of MmD is based on the presence of suggestive clinical features and multiple cores on muscle biopsy; muscle MRI may aid genetic testing as patterns of selective muscle involvement are distinct depending on the genetic background. Mutational analysis of the RYR1 or the
SEPN1
gene may provide genetic confirmation of the diagnosis. Management is mainly supportive and has to address the risk of marked respiratory impairment in
SEPN1
-related MmD and the possibility of malignant hyperthermia susceptibility in RYR1-related forms. In the majority of patients, weakness is static or only slowly progressive, with the degree of respiratory impairment being the most important prognostic factor.
...
PMID:Multi-minicore Disease. 1763 Oct 35
Congenital myasthenic syndromes (CMS) are a heterogeneous group of diseases of the neuromuscular junction caused by compromised synaptic transmission. Clinical features include early-onset weakness of limbs and oculobulbar muscles resulting in hypotonia, bulbar paresis, ptosis, and hypoventilation. The first dropped head syndrome in children were detected in 2 patients with LMNA and
SEPN1
mutations. We report a 17-month-old boy with dropped head and limb-girdle weakness, who had no ptosis or
ophthalmoplegia
at presentation. We performed whole exome sequencing, which revealed a homozygous missense variant in the AGRN gene c.5023G>A, p.Gly1675Ser in the LG2 domain, which is predicted to be likely disease causing by in silico tools. Agrin is known to play a critical role in the development and maintenance of the neuromuscular junction. Agrin-related CMS is one of the rarest subtypes. Of note, our patient is the first described patient with agrin-related CMS with dropped head phenotype.
...
PMID:A Novel Missense Variant in the AGRN Gene; Congenital Myasthenic Syndrome Presenting With Head Drop. 2822 5