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GTR Home > Conditions/Phenotypes > Down syndrome

Down syndrome

Synonyms
T21
Modes of inheritance
Not genetically inherited (Orphanet)

Summary

Down syndrome, the most frequent form of mental retardation caused by a microscopically demonstrable chromosomal aberration, is characterized by well-defined and distinctive phenotypic features and natural history. It is caused by triplicate state (trisomy) of all or a critical portion of chromosome 21. [from OMIM]

Available tests

97 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (96 available)

Cytogenetics Tests

Molecular Genetics Tests

Research tests

Clinical features

Help
Imported from Human Phenotype Ontology (HPO)

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Reviews

Clinical resources

Practice guidelines

  • NSGC, 2021
    National Society of Genetic Counselors Position Statement: Prenatal Cell-Free DNA Screening
  • ACMG ACT, 2021
    American College of Medical Genetics and Genomics Noninvasive Prenatal Screening via Cell-Free DNA ACT Sheet, Trisomy 21/Down syndrome: Positive Cell Free DNA Screen, 2021

Molecular resources

Consumer resources

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