Question: What is (are) Northern epilepsy ?
Answer: Northern epilepsy is a rare condition that affects the nervous system. Signs and symptoms of the condition generally develop between ages 5 and 10 years and may include recurrent seizures, mild intellectual disability, and motor abnormalities (i.e. problems with coordination and balance). Some affected people may also experience decreased visual acuity. Northern epilepsy is caused by changes (mutations) in the CLN8 gene and is inherited in an autosomal recessive manner. Treatment options are limited to therapies that can help relieve some of the symptoms.
Source: GARD

Question: What are the symptoms of Northern epilepsy ?
Answer: What are the signs and symptoms of Northern epilepsy? The Human Phenotype Ontology provides the following list of signs and symptoms for Northern epilepsy. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Ataxia - Autosomal recessive inheritance - Cerebellar atrophy - Cerebral atrophy - Curvilinear intracellular accumulation of autofluorescent lipopigment storage material - Delayed speech and language development - Developmental regression - EEG abnormality - Increased neuronal autofluorescent lipopigment - Myoclonus - Progressive visual loss - Seizures - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD