Analysis of the potassium voltage-gated channel subfamily Q member 1 gene in sudden unexplained deaths in a South African population

Abstract

This research aims to analyse the KCNQ1 gene in sudden unexpected deaths in a young South African population, to better understand the prevalence of variations within this gene. The KCNQ1 gene is a potassium ion channel protein, which is found in cardiac cells. Variations within this gene have been linked to cardiac channelopathies such as long and short QT syndromes. This research extracted DNA from blood samples of 66 deceased individuals received from the Pretoria Medico-Legal Laboratory, who were under the age of 50, and 19 control samples, received from volunteers who had signed informed consent. The exons of the KCNQ1 gene were optimised using primers and real-time PCR to be able to group similar cases together using HRM analysis. One case from each similarity group was sequenced. The respective chromatogram results, from the Sanger sequencing, were then used to determine if any variations were present. The variations found were then compared to previously published results to determine if they were novel. Intronic and exonic variants were found; all the variants were classified as benign. These findings showed that this gene may not be susceptible to pathogenic variations. However, an exon did have a prevalent variation, which could indicate the exon as a variable region, warranting further investigation.