To describe a case of Jaberi Elahi Syndrome (JABELS) due to a novel gene variant, and outline the clinical course.
JABELS is a rare autosomal recessive neurodevelopmental disorder characterized by impaired intellectual development, abnormal hand-foot posturing, dysmorphic facies and growth retardation. MRI brain typically shows corpus callosal abnormalities, cerebellar hypoplasia and white matter atrophy. Nearly 20 mutations of the GTPBP2 gene have been associated with JABELS, and more variants continue to be described. This case demonstrates a novel missense mutation producing a phenotype consistent with JABELS, and illustrates the clinical course of this condition.
A 6-month-old non-consanguineous female infant presented with global developmental delay, seizures and lower limb spasticity. The patient was born at term and the postnatal course was complicated by respiratory distress. Coarse facies, microcephaly, epicanthal folds, hairy pinnae, and a long philtrum with hypertelorism were evident on examination. Motor examination showed regression with lack of neck holding, and limb dystonia. MRI brain revealed abnormal myelination of the posterior limb of the internal capsule with no other malformations. A septal defect and patent ductus arteriosus were identified on echocardiography. Whole exome sequencing showed a novel homozygous missense mutation in exon 7 of the GTPBP2 gene (chr6:g.43624534G>T), similar to other mutations in this gene previously reported in JABELS.
At 19 months, the patient continued to have clusters of myoclonic spasms and tonic seizures despite treatment. She was admitted for recurrent seizures and decreased activity at 26 months. Interictal EEG was normal. She was discharged on brivaracetam and clobazam, and continues to have occasional breakthrough episodes.
This case describes a novel gene variant associated with JABELS, and adds to the limited fund of knowledge on the clinical presentation and genetic causes of this extremely rare disorder.