Lodder-Merla syndrome type 1 with impaired intellectual development and cardiac arrhythmia

A syndrome that is characterized by delayed psychomotor development, severe intellectual disability with poor or absent speech, and bradycardia and/or cardiac sinus arrhythmias and that has_material_basis_in homozygous or compound heterozygous mutation in the

A syndrome that is characterized by delayed psychomotor development, severe intellectual disability with poor or absent speech, and bradycardia and/or cardiac sinus arrhythmias and that has_material_basis_in homozygous or compound heterozygous mutation in the GNB5 gene on chromosome 15q21.

Signs and symptoms

• Delayed speech and language development
• Bradycardia
• Sick sinus syndrome
• Global developmental delay
• Intellectual disability
• Nystagmus
• Hypotonia
• Gastroesophageal reflux
• Seizure
• Abnormal electroretinogram

Also known as: GNB5-related intellectual disability-cardiac arrhythmia syndrome; intellectual developmental disorder with cardiac arrhythmia