A single strand conformation polymorphism heteroduplex (SSCP/HD) method for detection of mutations in 15 exons of the KVLQT1 gene, associated with long QT syndrome

Congenital long QT syndrome (LQTS) is characterised by prolongation of the QT interval on ECG and cardiac arrhythmias, syncopes and sudden death. A ra pid and reliable genetic diagnosis of the disease may be of great importanc e for diagnosis and treatment of LQTS. Mutations in the KVLQT1 gene, encodi ng a potassium-channel subunit of importance for the depolarisation of card iac myocytes, is believed to be associated with 50% of all LQTS cases. Our data confirms that KvLQT1 isoform 1 is encoded by 16 exons, and not 15, as reported previously. We have used genomic DNA sequences to design intronic PCR primers for amplification of 15 exons of KVLQT1 and optimised a non-rad ioactive single stranded conformation polymorphism/heteroduplex (SSCP/HD) m ethod for detection of mutations in KVLQT1. The sensitivity of the method w as 100% when it was tested on 15 in vitro constructed mutants. By multiplex ing the PCR amplification of KVLQT1, it is possible to cover all 15 exons i n four PCR reactions. (C) 1999 Elsevier Science BN. All rights reserved.