Since chromosomal analysis or karyotype testing is not a routine investigation when epilepsy first presents, the diagnosis of r(20) syndrome may be delayed or go unrecognized. We ask that you please consider chromosomal analysis if you have a patient (age 0-17) with the following symptoms:

  • normal childhood development until onset of epilepsy
  • medically refractory epilepsy with no etiology identified
  • predominantly complex partial seizures
  • Lennox-Gastaut-like features with no etiology identified
  • frequent subtle nocturnal seizures (SNS) and/or subtle nocturnal frontal lobe seizures (SNFL)
  • EEG showing prolonged high voltage frontally dominant slowing intermixed with spikes or sharp waves
  • EEG showing overlapping features of continuous slow spike and wave discharges in sleep (CSWS) and electrical status epilepticus in sleep (ESES)
  • no family history of chromosomal anomaly
  • no dysmorphism or other congenital malformations
  • cognitive impairment/learning difficulties/mild retardation


If you know of patients with r(20) syndrome, we ask that you tell their families about our Foundation and let them know that they are not alone. Our organization promotes new research and we hope to provide as much information about this syndrome as possible.
Please visit our website, and feel free to contact the Foundation at