Ring chromosome 14 syndrome

Other names: Ring 14, Ring chromosome 14
Formation of a ring chromosome.
Symptoms| Seizures, intellectual disability[1]
Causes| Caused by a chromosomal abnormality[1]
Diagnostic method| MRI, EEG[2]
Treatment| Anticonvulsive medication[2]

Ring chromosome 14 syndrome is a very rare human chromosome abnormality. It occurs when one or both of the telomeres that mark the ends of chromosome 14 are lost allowing the now uncapped ends to fuse together forming a ring chromosome. It causes a number of serious health issues.[1][3][4]

## Contents

* 1 Symptoms and signs
* 2 Cause
* 3 Diagnosis
* 4 Management
* 5 Epidemiology
* 6 See also
* 7 References
* 8 Further reading
* 9 External links

## Symptoms and signs[edit | edit source]

Male (VII) shows downslanting palpebral fissures, prominent nose, broad nasal bridge, thin upper lip (also hypotrophy of the of the lower limbs)

The most common symptoms are intellectual disability and recurrent seizures developing in infancy or early childhood. Typically the seizures are resistant to treatment with anti-epileptic drugs. Other symptoms may include:[1][5]

* Microcephaly
* Lymphedema
* Facial abnormalities
* Immune deficiencies
* Abnormalities of retina
* Slow growth
* Short stature
* Short neck
* Abnormalities of skin coloration
* Myoclonic seizures
* Bladder control problems
* Hypotonia
* Mental retardation

## Cause[edit | edit source]

The syndrome is caused by the loss of genetic material near the end of the long arm (q) of chromosome 14 . The break that causes the telomere(s) to be lost occurs near the end of the chromosome, and is called a constitutional ring. These rings arise spontaneously ( it is rarely inherited).[4][1][6][2]

The genetic abnormality occurs randomly in sperm or egg cells or it may occur in early embryonic growth, if it occurs during embryonic growth the ring chromosome may be present in only some of a person's cells.[medical citation needed]

* Telomer-structure

* Chr 14

## Diagnosis[edit | edit source]

Diagnosis is achieved by examining the structure of the chromosomes through karyotyping;[7] while once born, one can do the following to ascertain a diagnosis of the condition:[2]

* MRI
* EEG

## Management[edit | edit source]

[8] A type of anticonvulsant(Carbamazepine)

In terms of the management of ring chromosome 14 syndrome, anticonvulsive medication for seizures, as well as, proper therapy to help prevent respiratory infections in the affected individual are management measures that can be taken.[2]

## Epidemiology[edit | edit source]

Ring chromosome 14 syndrome is extremely rare, the true rate of occurrence is unknown (as it is less than 1 per 1,000,000), but there are at least 50 documented cases in the literature.[9]

## See also[edit | edit source]

* Ring chromosome 18 syndrome
* Ring chromosome 20 syndrome

## References[edit | edit source]

1. ↑ 1.0 1.1 1.2 1.3 1.4 Reference, Genetics Home. "ring chromosome 14 syndrome". Genetics Home Reference. Archived from the original on 2017-03-17. Retrieved 2017-03-17.
2. ↑ 2.0 2.1 2.2 2.3 2.4 Disorders, National Organization for Rare (2003). NORD Guide to Rare Disorders. Lippincott Williams & Wilkins. p. 64\. ISBN 9780781730631. Archived from the original on 2023-10-20. Retrieved 2023-10-02.
3. ↑ "Chromosome Abnormalities Fact Sheet". National Human Genome Research Institute (NHGRI). Archived from the original on 17 March 2017. Retrieved 17 March 2017.
4. ↑ 4.0 4.1 "OMIM Entry - # 616606 - RING CHROMOSOME 14 SYNDROME". omim.org. Archived from the original on 2021-03-23. Retrieved 2017-03-17.
5. ↑ Zollino, Marcella; Ponzi, Emanuela; Gobbi, Giuseppe; Neri, Giovanni (2012-05-01). "The ring 14 syndrome". European Journal of Medical Genetics. 55 (5): 374–380. doi:10.1016/j.ejmg.2012.03.009. ISSN 1878-0849. PMID 22564756. – via ScienceDirect (Subscription may be required or content may be available in libraries.)
6. ↑ Kelly, Evelyn B. (2013-01-07). Encyclopedia of Human Genetics and Disease. ABC-CLIO. p. 729\. ISBN 9780313387135. Archived from the original on 2023-10-20. Retrieved 2023-10-02.
7. ↑ "Ring chromosome 14 - Conditions - GTR - NCBI". www.ncbi.nlm.nih.gov. Archived from the original on 2017-03-26. Retrieved 2017-03-21.
8. ↑ Wallace, Sheila J.; Farrell, Kevin (2004-02-27). Epilepsy in Children, 2E. CRC Press. p. 354\. ISBN 9780340808146.
9. ↑ RESERVED, INSERM US14 -- ALL RIGHTS. "Orphanet: Ring chromosome 14". www.orpha.net. Archived from the original on 17 March 2017. Retrieved 17 March 2017.

## Further reading[edit | edit source]

* Disorders, National Organization for Rare (2003-01-01). NORD Guide to Rare Disorders. Lippincott Williams & Wilkins. ISBN 9780781730631. Archived from the original on 2023-10-20. Retrieved 2023-10-02.
* Zollino M.; Seminara L.; Orteschi D.; Gobbi G.; Giovannini S.; Della Giustina E.; Frattini D.; Scarano A.; Neri G. (2009). "The Ring14 Syndrome: Clinical and Molecular Definition" (PDF). American Journal of Medical Genetics. 149A (6): 1116–1124. doi:10.1002/ajmg.a.32831. PMID 19441122. S2CID 22919033. Archived (PDF) from the original on 2022-08-18. Retrieved 2023-10-02.

## External links[edit | edit source]

Classification|

* ICD-10: Q93.2
* OMIM: 616606
* DiseasesDB: 34753

|

External resources|

* Orphanet: 1440

* v
* t
* e

Chromosome abnormalities

Autosomal|

| Trisomies/Tetrasomies|

* Patau syndrome
* 13
* Edwards syndrome
* 18
* Down syndrome
* 21

* Warkany syndrome 2
* 8
* Trisomy 9
* Tetrasomy 9p
* Trisomy 16
* Cat eye syndrome/Trisomy 22
* 22

|

Monosomies/deletions|

* (1q21.1 copy number variations/1q21.1 deletion syndrome/1q21.1 duplication syndrome/TAR syndrome/1p36 deletion syndrome)
* 1
* Wolf–Hirschhorn syndrome
* 4
* Cri du chat syndrome/Chromosome 5q deletion syndrome
* 5
* Williams syndrome
* 7
* Jacobsen syndrome
* 11
* Miller–Dieker syndrome/Smith–Magenis syndrome/17q12 microdeletion syndrome
* 17
* DiGeorge syndrome
* 22
* 22q11.2 distal deletion syndrome
* 22
* 22q13 deletion syndrome
* 22

* genomic imprinting
* Angelman syndrome/Prader–Willi syndrome (15)

* Distal 18q-/Proximal 18q-

X/Y linked|

| Monosomy|

* Turner syndrome (45,X)

|

Trisomy/tetrasomy,
other karyotypes/mosaics|

* Klinefelter syndrome (47,XXY)
* XXYY syndrome (48,XXYY)
* XXXY syndrome (48,XXXY)
* XXXXY syndrome (49,XXXXY)

* Trisomy X (47,XXX)
* Tetrasomy X (48,XXXX)
* Pentasomy X (49,XXXXX)

* XYY syndrome (47,XYY)
* XYYY syndrome (48,XYYY)
* XYYYY syndrome (49,XYYYY)

* 45,X/46,XY
* 46,XX/46,XY

Translocations|

| Leukemia/lymphoma|

| Lymphoid|

* Burkitt's lymphoma t(8 MYC;14 IGH)
* Follicular lymphoma t(14 IGH;18 BCL2)
* Mantle cell lymphoma/Multiple myeloma t(11 CCND1:14 IGH)
* Anaplastic large-cell lymphoma  t(2 ALK;5 NPM1)
* Acute lymphoblastic leukemia

|

Myeloid|

* Philadelphia chromosome t(9 ABL; 22 BCR)
* Acute myeloblastic leukemia with maturation t(8 RUNX1T1;21 RUNX1)
* Acute promyelocytic leukemia t(15 PML,17 RARA)
* Acute megakaryoblastic leukemia t(1 RBM15;22 MKL1)

Other|

* Ewing's sarcoma t(11 FLI1; 22 EWS)
* Synovial sarcoma t(x SYT;18 SSX)
* Dermatofibrosarcoma protuberans t(17 COL1A1;22 PDGFB)
* Myxoid liposarcoma t(12 DDIT3; 16 FUS)
* Desmoplastic small-round-cell tumor t(11 WT1; 22 EWS)
* Alveolar rhabdomyosarcoma t(2 PAX3; 13 FOXO1) t (1 PAX7; 13 FOXO1)

Other|

* Fragile X syndrome
* Uniparental disomy
* XX male syndrome/46,XX testicular disorders of sex development
* Marker chromosome
* Ring chromosome
* 6; 9; 14; 15; 18; 20; 21, 22

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