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syndromic X-linked intellectual disability 34

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The information provided on this page is for informational purposes only. The National Organization for Rare Disorders (NORD) does not endorse the information presented. The content has been gathered in partnership with the MONDO Disease Ontology. Please consult with a healthcare professional for medical advice and treatment.

Disease Overview

Macrocephaly-intellectual disability-left ventricular non compaction syndrome is a rare, genetic, syndromic intellectual disability characterized by motor and cognitive developmental delay with language impairment, macrocephaly, hypotonia, dysmorphic facial features (including long face, slanting palpebral fissures and prominent, flattened nose) and left ventricular noncompaction cardiomyopathy. Patients also present skeletal abnormalities (e.g. scoliosis, finger clinodactyly, pes planus), slender build and shy behavior. Strabismus and various neurological signs (including ataxia, tremor and hyperreflexia) may be associated, as well as epilepsy, autism and MRI findings showing a small cerebellum and abnormalities of the corpus callosum. A phenotypic variant with no cardiac involvement has been reported.

Synonyms

  • MRXS34
  • MRXSML
  • NONO X-linked syndromic intellectual disability
  • X-linked syndromic intellectual disability caused by mutation in NONO
  • intellectual developmental disorder, X-linked syndromic 34
  • intellectual disability, X-linked, syndromic 34
  • intellectual disability, X-linked, syndromic type 34
  • intellectual disability, X-linked, syndromic, Mircsof-Langouet type
  • macrocephaly-intellectual disability-left ventricular non compaction syndrome
  • mental retardation, X-linked, syndromic 34
  • mental retardation, X-linked, syndromic type 34
  • mental retardation, X-linked, syndromic, Mircsof-Langouet type
  • syndromic X-linked intellectual disability Mircsof-Langouet type
  • syndromic X-linked intellectual disability type 34
  • syndromic X-linked mental retardation Mircsof-Langouet type
GARD Disease Summary

The Genetic and Rare Diseases Information Center (GARD) has information and resources for patients, caregivers, and families that may be helpful before and after diagnosis of this condition. GARD is a program of the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health (NIH).

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Orphanet

Orphanet has a summary about this condition that may include information on the diagnosis, care, and treatment as well as other resources. Some of the information and resources are available in languages other than English. The summary may include medical terms, so we encourage you to share and discuss this information with your doctor. Orphanet is the French National Institute for Health and Medical Research and the Health Programme of the European Union.

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OMIM

Online Mendelian Inheritance In Man (OMIM) has a summary of published research about this condition and includes references from the medical literature. The summary contains medical and scientific terms, so we encourage you to share and discuss this information with your doctor. OMIM is authored and edited at the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine.

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