Abstract: Objective To investigate KCNQ1, KCNH2, KCNE1 and KCNE2 gene variants in the cases of sudden manhood death syndrome （SMDS）. Methods One hundred and sixteen sporadic cases of SMDS and one hundred and twenty-five healthy controlled samples were enrolled. Genomic DNA was extracted from blood samples. Gene variants of KCNQ1, KCNH2, KCNE1 and KCNE2 were screened by direct sequencing. Results A total of 14 mutations and 14 SNP were detected. Two non-synonymous mutations of them were newfound. There was no non-synonymous mutation found in the control group. Conclusion There are KCNQ1, KCNH2, KCNE1 and KCNE2 gene variants found in Chinese SMDS cases. KCNQ1, KCNH2, KCNE1 and KCNE2 gene mutation may correlate partly with the occurrence of some cases of the SMDS in China.

Key words: forensic genetics, mutation, potassium channels, sudden manhood death syndrome