Breakage of the ERBB4-gene in a girl with reciprocal translocation t(1;2) (p22.3;q34) – Is there a relation to severe infantile epilepsy?

Abstract

We report on a now 4 ½ year old female patient, who has been suffering from severe epilepsy from the age of 6 weeks onward. Beside mild hypertrichosis no stigmata or dysmorphic signs were detected. Cranial imaging, routine CSF analysis and biochemical screening for amino- and organoacidopathies were normal. Seizures initially were therapyresistant to pyridoxine, phenobarbitone and valproate but by age 3 years could be controlled by a low dose combination of valproate, clonazepam and topiramate. Developmental delay was evident from early infancy with marked delay of motor milestones and severe mental retardation. At the age of 4 years she had poor visual contact, absent speech, insensitivity to pain and generalized dyspraxia. Mild muscular hypotonia with scoliotic posture of the upper spine was present, deep tendon reflexes were preserved. EEG showed a monomorphic pattern of rhythmic high-voltage alpha/theta activity with lack of fronto-occipital differentiation and of epileptic discharges. Motor nerve conduction velocity as well as cranial MRI were normal.