Brugada syndrome and p.E61X_RANGRF.

BACKGROUND Brugada syndrome is an inherited cardiac condition transmitted with an autosomal dominant pattern which can lead to sudden cardiac death from malignant ventricular arrhythmias. The RANGRF gene has recently been proposed to be associated with Brugada syndrome. This gene encodes the MOG1 protein, a co-factor required for the full functioning of the cardiac sodium channel Nav1.5. The nonsense p.E61X genetic variation in the RANGRF gene has been postulated as responsible for Brugada syndrome although no clear association has been established. METHODS We clinically and genetically evaluated a Spanish family diagnosed with Brugada syndrome. A comprehensive genetic analysis of all genes to date responsible for Brugada syndrome was performed in the index case. RESULTS The index case was clinically diagnosed with Brugada syndrome after flecainide test. We identified a nonsense variation (p.E61X) in the index case and in other five family members. All of them showed a normal electrocardiogram in basal conditions. Flecainide test unmasked a type 1 Brugada syndrome electrocardiogram only in two of the relatives. CONCLUSIONS We suggest that p.E61X_RANGRF is a rare genetic variation with an uncertain role in Brugada Syndrome. Further studies must be performed to elucidate the potential pathogenic role of p.E61X_RANGRF in Brugada Syndrome.