First report of genetic variants detected in Argentinian patients with clinical Long QT Syndrome diagnosis

Abstract

AbstractBackgroundLong QT Syndrome (LQTS) is a genetic cardiac condition in which disease severity and response to pharmacological treatments vary according to genetic variations. In Argentina, most of the LQTS diagnoses are made by clinical exploration and ECG analysis. In this work, we evaluated a group of subjects from our community to correlate their clinical LQTS diagnosis with genetic modifications.Material and methods: Using gDNA isolation, PCR, and exome sequencing, we screened the coding sequences of theKCNQ1, KCNH2, andSCN5Agenes in the studied cohort.ResultsWe identified several DNA changes, among synonymous and non-synonymous, most of them previously described in the literature. In addition, we found a non reported alteration in the sequence ofKCNQ1sequence that suggests the lack (deletion) of an exon or a large part of it indicating exon deletion. 16 which did not allow us to amplify it.ConclusionsThis is the first report of genetic variations in LQTS-associated genes in Argentina. The variations detected could explain the prolongation of the QT interval observed in the ECG of some of the individuals or those with a suspicious family history and could improve treatment, making it more rational as well as providing genetic counselling to first-degree relatives.HighlightsGenetic screening correlates with clinical diagnosis in LQT patientsStudied cases carry more than one variation in at least 2 genes simultaneouslyA Non-reported variation in KCNQ1 exon 16 was founded in one case