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Ring chromosome 16

MedGen UID:
Concept ID:
Disease or Syndrome
Synonyms: chromosome 16 ring; R16; Ring 16; ring chromosome 16; Ring chromosome 16 syndrome; Ring chromosome type 16
SNOMED CT: Ring chromosome 16 syndrome (763406004); Ring chromosome 16 (763406004)
Monarch Initiative: MONDO:0019909
Orphanet: ORPHA96178


A rare chromosomal anomaly syndrome resulting from the partial deletion of chromosome 16, with characteristics of pre and postnatal growth delay, severe developmental delay, intellectual disability, speech delay, and craniofacial dysmorphism (e.g. microcephaly, hypertelorism, downslanted palpebral fissures, ptosis, telecanthus, low set and dysmorphic ears, broad flat nasal bridge, down-turned mouth corners, high palate, retrognathia). Patients may also present congenital cataract, mild synophrys, hypotonia, and poor social contact. Congenital heart anomalies (e.g. ventricular septal defect, patent ductus arteriosus) have also been reported. [from SNOMEDCT_US]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVRing chromosome 16

Professional guidelines


Koza SA, Tabet AC, Bonaglia MC, Andres S, Anderlid BM, Aten E, Stiefsohn D; European Phelan-McDermid syndrome consortium, Evans DG, van Ravenswaaij-Arts CMA, Kant SG
Eur J Med Genet 2023 Jul;66(7):104773. Epub 2023 Apr 28 doi: 10.1016/j.ejmg.2023.104773. PMID: 37120077
Vigneswaran TV, Allan L, Charakida M, Durward A, Simpson JM, Nicolaides KH, Zidere V
Prenat Diagn 2018 Dec;38(13):1055-1061. doi: 10.1002/pd.5388. PMID: 30421794
Razon Y, Berant M, Fogelman R, Amir G, Birk E
J Am Soc Echocardiogr 2014 Dec;27(12):1352-8. Epub 2014 Sep 17 doi: 10.1016/j.echo.2014.08.003. PMID: 25240492

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