Objective: To identify the gene mutation in a Chinese family with congenital long QT syndrome (LQTS) and predict the changes of the secondary structure of the protein.
Methods: Polymerase chain reaction and DNA sequencing were used to screen for KCNH2 mutation in the proband. After the mutation was identified, KCNH2 gene of the family members was screened by multiplex PCR with site-specific primers. Network analysis software was used to predict the secondary structure of the KCNH2 protein.
Results: A novel heterozygous missense mutation of F463L(GenBank accession no.EU218526) located at the transmembrane domain S2 of KCNH2 was detected. The mutation did not result in the change of the transmembrane domain, but altered the hydrophobicity and secondary structure of the protein.
Conclusion: The novel mutation identified in this study has enriched the GenBank data of ion channel gene mutation in LQTS. The changes of the secondary structure caused by the gene mutation were analyzed by Mfold and TMHMM software, which may help to understand LQTS.