Revealing The Heterogeneity Of Sporadic And Syndromic Thoracic Aortic Aneurysms Based On WES And Transcriptome

Objective(s): Different subtypes of TAA exhibit significant heterogeneity among prevention,treatment,and prognosis,and these heterogeneity are increasingly important in the research of TAA diseases."Through Whole Exome Sequencing(WES)and transcriptome analysis,the heterogeneity of sporadic and syndromic thoracic aortic aneurysms(TAA)was revealed,and attempts were made to identify significantly differentially expressed genes between the two subtypes,looking for heterogeneity between sporadic and syndromic thoracic aortic aneurysms from the perspectives of differentially expressed genes,module analysis,and enrichment pathways.",To provide new research ideas for the diagnosis,treatment,and prognosis of different subtypes of TAA.Methods:1.The full exon sequencing data of 11 sporadic and 6 syndrome type TAA samples collected were analyzed.(1)Quality control analysis of sequencing data;(2)Quantitative analysis of mutations in different groups of whole exon somatic cells;(3)Somatic cell mutation pattern analysis:(4)Analysis of copy number variation in different groups of somatic cells.2.The transcriptome sequencing data of 11 sporadic and 6 syndrome type TAA samples collected were analyzed.(1)Processing the data and visualizing differentially expressed genes(DEGs),constructing and enriching protein protein interaction networks(PPI)for DEGs;(2)Enrichment and analysis of gene sets and construction of drug analysis networks;(3)Use the weighted correlation network analysis(WGCNA)method to obtain the modules most relevant to disease heterogeneity,and conduct enrichment analysis on the most relevant modules;(4)Screening the common key genes of the two subtypes using machine learning algorithms and performing recipient operating characteristic curve(ROC)analysis of their expression levels;(5)Calculate the correlation of key genes in sporadic and syndrome type TAA,and conduct enrichment analysis of key genes in different subtypes of TAA.Results:1.The quality control indicates that the sequencing data is reasonable and can meet subsequent analysis.2.Detect the mutation landscape of all genes,indicating that mistranslated mutations account for the majority.DNAH5,CNN2,and PLEKHM2 are the genes with the top 3 mutation times.The most common types of point mutations are C>T,T>C,and the largest number of samples are patients labeled KLKA.The proportion of comparison notes can be obtained in the db SNP database and the 1000 G database.Further comparison using existing databases confirms the reliability of the mutation data,which also indicates that there is significant heterogeneity in the number of somatic mutations in patients with different subtypes of TAA.3.Somatic mutation pattern analysis was performed on the data of 17 patients with TAA.The results were divided into two sigs,and we compared the two sigs with each single base substitution feature in the COSMIC(Catalog Of Somatic Mutations In Cancer)database.The similarity is above 0.6,and we believe that single base substitution mutations are similar.4.Using CNVkit software for exon sequencing and comparison,BAM files were obtained to detect regions with copy number changes in the genome of each sample.The results showed that many regions had significant copy number amplification or deletion.The number of copies with copy number amplification and copy number deletion in each sample was separately counted,indicating that there was a small difference in copy number between the two different subtypes.5.Through differential expression analysis and comparison of transcriptome sequencing data,we found 98 upregulated differentially expressed genes and 91 downregulated differentially expressed genes,and conducted enrichment analysis on DEGs and construction of a PPI network.The enrichment entries were mainly related to bacterial defense reactions,secretory granule cavities,and glycosaminoglycan binding.6.Analysis of gene pool enrichment revealed that it was mainly concentrated in the response of cells to biological stimuli,binding of nucleosomes and glycosaminoglycans,and the construction of target gene-drug networks.It was found that interferon,gibberellin,and tininib drugs might have new discoveries in the treatment of sporadic active thoracic aneurysm and syndrome type thoracic aortic aneurysm in the future.7.Through the construction of a co expression network using WGCNA,it was found that green modules were significantly correlated with sporadic thoracic aortic aneurysm and syndrome thoracic aortic aneurysm.The enrichment analysis of key modules and the construction of a PPI network suggested that they were mainly enriched in pathways such as vascular development,inflammatory response,and extracellular matrix binding.8.Through machine learning,two key genes,PHLDA3 and IL23 R,were screened,and they were also significantly differentially expressed between the syndrome type and sporadic type TAA groups.Through correlation analysis,it was found that these two genes had significant correlation in syndrome type TAA.Subsequent analysis of expression levels and ROC curves showed that PHLDA3 was significantly lower expressed in comprehensive thoracic aortic aneurysm,and IL23 R was significantly higher expressed in comprehensive thoracic aortic aneurysm.IL23 R has relatively good diagnostic ability.Enrichment analysis of the above two key genes showed that in sporadic TAA,they were mainly enriched in ribosome,citrate cycle,proteasome,fatty acid metabolism,oxidative phosphorylation,and other pathways.In syndrome type TAA,it is mainly enriched in pathways such as glycosaminoglycan biosynthesis of chondroitin sulfate,glycosaminoglycan degradation,RNA degradation,and cell cycle.Conclusion:This study found that WES and transcriptome sequencing can reveal the heterogeneity of different subtypes of TAA.From the analysis of WES,it can be seen that mistranslated mutations account for the majority in different subtypes of TAA,and DNAH5,C1NN2,and PLEKHM2 are the genes with the top 3 mutation times.Through comparison,it can be shown that there is significant heterogeneity in the number of somatic mutations in patients with different subtypes of TAA.From transcriptome analysis,it can be seen that PHLDA3 and IL23 R are significantly differentially expressed genes in syndrome type and sporadic type TAA groups,and the pathways enriched in different subtypes of TAA also have significant heterogeneity.