Cardiac Disease Associated Genetic Variants in Yi Nationality in Regions with High Incidence of Yunnan Sudden Unexplained Death.

Abstract

Objective To explore the association of cardiac disease associated genetic variants and the high incidence of Yunnan sudden unexplained death （YNSUD） in Yi nationality. Methods The genomic DNA was extracted from peripheral blood samples collected from 205 Yi villagers from YNSUD aggregative villages （inpatient group） and 197 healthy Yi villagers from neighboring villages （control group）. Fifty-two single nucleotide variants （SNVs） of 25 cardiac disease associated genes were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. The SPSS 17.0 was used to analyze data. The pathogenicities of variants with differences between the two groups that have statistical significance were predicted by protein function prediction software PolyPhen-2 and SIFT. All villagers from inpatient group were given electrocardiogram （ECG） examination using a 12-lead electrocardiograph. Results The allele frequency and the genotype frequency of missense mutation DSG2 （rs2278792, c.2318G>A, p.R773K） of pathogenic genes of arrhythmogenic right ventricular cardiomyopathy （ARVC） in inpatient group was higher than that in control group （P<0.05）. Abnormal ECG changes were detected in 71 individuals （34.6%） in the inpatient group, among which 54 individuals carried R773K mutation, including clockwise （counterclockwise） rotation, left （right） axis deviation, ST segment and T wave alteration and heart-blocking. Conclusion Definite pathogenic mutations have not been found in the 52 cardiac disease genes associated SNVs detected in Yi nationality in regions with high incidence of YNSUD. The cause of high incidence of YNSUD in Yi nationality needs further study.