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Updated: May 6, 2026

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Novel mutations of KCNQ1 in Long QT syndrome
Sameera F Qureshi1, Altaf Ali, Venkateshwari Ananthapur
1Dept. of Genetics, University College of Science, Osmania University, Hyderabad 500007, Andhra Pradesh, India.
Background:
Autosomal recessive Long QT syndrome is characterized by prolonged QTc along with congenital bilateral deafness depends on mutations in K(+) channel genes. A family of a Long QT syndrome proband from India has been identified with novel indel variations.
Methods:
The molecular study of the proband revealed 4 novel indel variations in KCNQ1. In-silico analysis revealed the intronic variations has led to a change in the secondary structure of mRNA and splice site variations. The exonic variations leads to frameshift mutations. DNA analysis of the available family members revealed a carrier status.
Results And Conclusion:
It is thus predicted that the variations may lead to a change in the position of the splicing enhancer/inhibitor in KCNQ1 leading to the formation of a truncated S2-S3 fragment of KCNQ1 transmembrane protein in cardiac cells as well as epithelial cells of inner ear leading to deafness and aberrant repolarization causing prolonged QTc.
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