Short title of the study    
Phenotype of individuals with bi-allelic variants in FRRS1L

Targeted gene(s)/phenotype/disorder under study
 FRRS1L (OMIM 604574)

Summary (1000 letters max):
Bi-allelic variants in FRRS1L are associated with an epileptic-dyskinetic encephalopathy. Loss-of-function variants of FRRS1L disrupt synaptic AMPA reception function, resulting in a devastating neurological condition. Few patients are described in the literature, and detailed epileptic phenotyping is missing in the majority of them. In addition to the few families were are currently following in our hospital, we want to collect more patients with bi-allelic variants in FRRS1L in order to define the phenotype-genotype correlation. We would like to collect clinical, neurophysiological and neuroimaging information. For variants of specific interest, those being recurrent in specific populations, we also want to reanalyse DNA in order to identify potential founder mutations.

Coordinating clinicians
Reza Maroofian –
Matthias De Wachter –

Institution (dept, hospital, City)
Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
Department of Pediatric Neurology, Antwerp University Hospital, University of Antwerp, Edegem, Belgium

Specific requirements beyond clinical data and genotype data sharing:

  • Re-analysis of DNA samples: Yes, in selected cases (variants of specific interest)
  • Resampling of patients: N
  • Linked to a translational/basic research project: N