15q26 overgrowth syndrome
What are symptoms of 15q26 overgrowth syndrome?
Common symptoms of 15q26 overgrowth syndrome are a characteristic facial appearance, severe intellectual disability, craniosynostosis and a unique appearance of the fingers. The characteristic facial appearance can include:
- a prominent forehead (called frontal bossing)
- a prominent nose
- a broad nasal root (the top portion of the nose located between the eyes)
- short palpebral fissures (palpebral fissures are the openings between the inner and outer corners of the eye)
- down-slanting palpebral fissures (palpebral fissures that slant downward from the nose)
- low-set ears
Craniosynostosis is a birth defect that happens when the bones of a baby's skull grow together, or fuse, earlier that they should. This causes the head to be misshapen and does not allow the brain to grow into its normal shape. The degree of intellectual disability seen in 15q26 syndrome is severe; several patients who have been described with this condition never learned how to talk. The characteristic symptoms of the fingers seen in 15q26 overgrowth syndrome are arachnodactyly and camptodactyly. Arachnodactyly means long, slender fingers that are described as "spider-like". Camptodactyly is when the fingers are permanently bent and cannot be completely straightened. Other symptoms that have been seen in 15q26 overgrowth syndrome include overgrowth, kidney problems, spine abnormalities like scoliosis, heart defects and hearing loss.
The best type of doctor to figure out if someone has 15q26 overgrowth syndrome is a medical geneticist (a doctor specially trained to diagnose and treat genetic conditions). Medical geneticists can be found by asking for recommendations from your regular doctor, or by using the American College of Medical Genetics' Clinic Services Search Engine. In the "search by genetic service type(s)" heading, choose "General Genetic Services" from the "Clinic Service Type" drop down menu, and check the "General Genetics" box under "Clinic Services". If a child will be meeting with the geneticist, you may want to check the "Pediatric Genetics" box under "Clinic Services".
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