National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Ring chromosome 13


Other Names:
Chromosome 13 ring; Ring 13; R13
Categories:
Ring chromosome 13 is a rare chromosome abnormality in which the ends of chromosome 13 join together to form a ring shape. When a ring forms, there may be missing genes where the chromosome's ends fuse together. Therefore, the severity and symptoms associated with ring chromosome 13 vary from person to person, depending on the number of genes, and specific genes, involved. Most people with ring chromosome 13 also have cells with 46 normal chromosomes (this is called mosaicism), which can lessen the effect of the ring chromosome on growth and development.[1]

Signs and symptoms that may be present in a person with ring chromosome 13 include developmental delay, slow growth and short stature, feeding difficulties, learning difficulties, a small head size, abnormal formation or positioning of the feet and/or toes, and/or abnormalities of the palate (roof off the mouth). Depending on  how many genes are lost and how many normal cells a person has, additional features or birth defects may also be present.[1]

Ring chromosome 13 typically is not inherited, occurring sporadically during the formation of egg or sperm cells or shortly after the egg and sperm join together. In some cases, ring chromosome 13 is inherited from a parent.[1] Chromosome testing of parents can help determine whether the ring chromosome was inherited and whether future children have an increased chance to have a chromosome abnormality. Treatment for ring chromosome 13 depends on the signs and symptoms present in each person.
Last updated: 6/21/2018

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal facial shape
Unusual facial appearance
0001999
Growth delay
Delayed growth
Growth deficiency
Growth failure
Growth retardation
Poor growth
Retarded growth
[ more ] 		0001510
Intellectual disability, severe
Early and severe mental retardation
Mental retardation, severe
Severe mental retardation
[ more ] 		0010864
Microcephaly
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference
[ more ] 		0000252
30%-79% of people have these symptoms
Ambiguous genitalia
Ambiguous external genitalia
Ambiguous external genitalia at birth
Intersex genitalia
[ more ] 		0000062
Anteverted nares
Nasal tip, upturned
Upturned nasal tip
Upturned nose
Upturned nostrils
[ more ] 		0000463
Bifid scrotum
Cleft of scrotum
0000048
Depressed nasal bridge
Depressed bridge of nose
Flat bridge of nose
Flat nasal bridge
Flat, nasal bridge
Flattened nasal bridge
Low nasal bridge
Low nasal root
[ more ] 		0005280
Hypertelorism
Wide-set eyes
Widely spaced eyes
[ more ] 		0000316
Hypospadias 0000047
Macrotia
Large ears
0000400
Micropenis
Short penis
Small penis
[ more ] 		0000054
Primary hypothyroidism 0000832
Skeletal dysplasia 0002652
Wide nasal bridge
Broad nasal bridge
Broad nasal root
Broadened nasal bridge
Increased breadth of bridge of nose
Increased breadth of nasal bridge
Increased width of bridge of nose
Increased width of nasal bridge
Nasal bridge broad
Wide bridge of nose
Widened nasal bridge
[ more ] 		0000431
5%-29% of people have these symptoms
Abnormal renal physiology
Abnormal kidney function
Kidney function issue
[ more ] 		0012211
Abnormality of skin pigmentation
Abnormal pigmentation
Abnormal skin color
Abnormal skin pigmentation
Abnormality of pigmentation
Pigmentary changes
Pigmentary skin changes
Pigmentation anomaly
[ more ] 		0001000
Abnormality of the incisor 0000676
Absent foot 0011301
Alopecia
Hair loss
0001596
Anal atresia
Absent anus
0002023
Anencephaly 0002323
Aplasia/Hypoplasia of the thumb
Absent/small thumb
Absent/underdeveloped thumb
[ more ] 		0009601
Autism 0000717
Cafe-au-lait spot 0000957
Epicanthus
Eye folds
Prominent eye folds
[ more ] 		0000286
Frontal bossing 0002007
Generalized hypotonia
Decreased muscle tone
Low muscle tone
[ more ] 		0001290
High palate
Elevated palate
Increased palatal height
[ more ] 		0000218
Micrognathia
Little lower jaw
Small jaw
Small lower jaw
[ more ] 		0000347
Partial absence of foot 0030032
Posteriorly rotated ears
Ears rotated toward back of head
0000358
Short neck
Decreased length of neck
0000470
Short philtrum 0000322
Trigonocephaly
Triangular skull shape
Wedge shaped skull
[ more ] 		0000243
Urogenital sinus anomaly 0100779
1%-4% of people have these symptoms
Abnormality of the coagulation cascade 0003256
Agenesis of corpus callosum 0001274
Hypoplasia of the gallbladder 0005233
Retinoblastoma 0009919
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Last updated: 7/1/2020

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
  • Unique is a source of information and support to families and individuals affected by rare chromosome disorders. Click on the link to view information about ring chromosome 13.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Ring chromosome 13. Click on the link to view a sample search on this topic.

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  1. Ring 13. Unique. 2006; https://www.rarechromo.org/media/information/Chromosome%2013/Ring%2013%20FTNW.pdf.