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GTR Home > Conditions/Phenotypes > Language delay and attention deficit-hyperactivity disorder/cognitive impairment with or without cardiac arrhythmia

Language delay and attention deficit-hyperactivity disorder/cognitive impairment with or without cardiac arrhythmia

Synonyms
LODDER-MERLA SYNDROME, TYPE 2, WITH DEVELOPMENTAL DELAY AND WITH OR WITHOUT CARDIAC ARRHYTHMIA

Summary

Excerpted from the GeneReview: GNB5-Related Neurodevelopmental Disorder
GNB5-related neurodevelopmental disorder (GNB5-NDD) is characterized by a spectrum of neurodevelopmental phenotypes that range from severe-to-profound intellectual disability (ID; 31/41 reported individuals), to mild-to-moderate ID (5/41), to normal intellect with severe language disorder (5/41, one extended family). A unique and specific feature of GNB5-NDD – regardless of neurodevelopmental phenotype – is nearly universal bradycardia caused by sinoatrial node dysfunction (sick sinus syndrome). Most individuals with severe and profound ID have a developmental and epileptic encephalopathy with focal seizures or epileptic spasms, as well as visual impairment (central or retinal) with nystagmus, difficulty feeding, and gastroesophageal reflux disease. The risk of early mortality is increased.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Gemma Poke
Lynette Grant Sadleir
Giuseppe Merla
view full author information

Available tests

4 tests are in the database for this condition.

Clinical tests (4 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: GB5, HG2E, IDDCA, LADCI, LDMLS1, LDMLS2, gbeta5, GNB5
    Summary: G protein subunit beta 5

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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