Ring chromosome 14 syndrome

Ring chromosome 14 syndrome (also known as r(14) syndrome) is a rare chromosomal disorder in which one copy of chromosome 14 forms a ring structure, typically resulting from breakage and reunion at both ends of the chromosome with loss of genetic material from the distal portions. This ring formation leads to partial monosomy of chromosome 14, and the clinical consequences depend on the amount of deleted material and the degree of ring instability during cell division, which can cause mosaic monosomic or trisomic cell lines. The syndrome primarily affects the nervous system, with epilepsy being the hallmark feature. Seizures typically begin in infancy or early childhood and are often refractory (difficult to control), frequently presenting as early-onset epileptic encephalopathy. Other key clinical features include intellectual disability of variable severity, speech and language delay, microcephaly, retinal abnormalities (including retinitis pigmentosa-like changes), and distinctive but subtle facial features such as a flat nasal bridge, epicanthal folds, and a short philtrum. Growth retardation and hypotonia are also commonly observed. Some patients may develop recurrent infections due to immunological abnormalities, as the immunoglobulin heavy chain gene locus (IGH) is located on the long arm of chromosome 14. There is no cure for ring chromosome 14 syndrome. Treatment is primarily supportive and symptomatic, focusing on seizure management with antiepileptic medications, though seizures are often drug-resistant. Early intervention programs including physical therapy, occupational therapy, and speech therapy are important for optimizing developmental outcomes. Regular ophthalmological monitoring is recommended due to the risk of progressive retinal changes. Genetic counseling is advised for affected families.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Ring chromosome 14 syndrome