[PCR-based site-directed mutagenesis and recombinant expression plasmid construction of a SCN5A mutation (K317N) identified in a Chinese family with Brugada syndrome].

Objective: To perform PCR-based site-directed mutagenesis of a new SCN5A mutation (K317N) identified in a Chinese family with Brugada syndrome and construct the recombinant expression plasmid pRc/CMV-Hh1 containing the human cardiac sodium channel alpha subunit (hH1), mutant cDNA.
Methods: A pair of primers was designed according to the restricted sites Sse 8387I and Age I of the SCN5A sequence with the mismatches introduced into primers. Mutagenesis was performed in a single-step PCR, and the fragments amplified by PCR containing the mutation site were subcloned into the pRc/CMV-hH1 vector.
Results: Sequence analysis confirmed the presence of the desired mutation site, and a mutation from K (Lys) to N (Asn) in codon 317 was identified in the SCN5A gene, indicating the successful induction of the mutation at K317N of the SCN5A gene.
Conclusion: PCR site-directed mutagenesis is accurate and highly efficient, and the successfully constructed recombinant expression plasmid pRc/CMV-hH1 (K317N) may provide a molecular basis for further functional and genomic investigation of SCN5A.