Integrative analyses identify potential key genes and pathways in Keshan disease using whole-exome sequencing

Keshan disease (KD), an endemic heart disease with multifocal necrosis and replacement fibrosis of the myocardium,is still a nightmare situation for human health. However, molecular mechanism in the pathogenesis of KD remains unclear. Herein, blood samples were collected from 68 KD patients and 100 controls, and we systematically analyzed mutation profiles using whole-exome sequencing (WES). Causative genes of dilated cardiomyopathy (DCM), gene-based burden analysis, disease and pathway enrichment analysis, and protein-protein interaction (PPI) network analysis were performed. Of the 98 DCM-causative genes, 106 rare variants in 28 genes were detected in KD patients with minor allele frequency (MAF) < 0.001. Gene-based burden analysis, PPI network analysis, and automated Phenolyzer analysis were performed to prioritize 199 candidate genes, which combined with 98 DCM-causative genes, and reference genes from gene microarray or proteomics in KD. Then, 19 candidate pathogenic genes were selected, and 9 candidate genes were identified using PPI analysis, including HIF1A, GART, ALAD, VCL, DTNA, NEXN, INPPL1, NOS3, and JAK2. The 199 candidate genes were further analyzed using disease enrichment with CTD database and PPI analysis, and 21 candidate genes were identified. By combining with disease enrichment and PPI analysis, 7 Selenium (Se)-related genes were further identified, including ALAD, RBM10, GSN, GGT1, ADD1, PARP1, and NOS3. Based on the gene function and data validation, NEXN, TAF1C, FUT4, ALAD, ZNF608, and STX2 were the most likely pathogenic genes in KD. Notably, ALAD is the only candidate pathogenic gene identified by four different analyses, and its homozygous mutant mice could affect heart development and cause death.