Efficacy Of Analytical IMPATT (Integrated Mutation Profiling Of Actionable TAAD Targets) Methods In Identifying Familial Thoracic Aortic Aneurysms/Dissection

Objective:Thoracic aortic aneurysm / dissection(TAAD)is a large vascular disease with high mortality and insidious onset;TAAD is closely related to genetic factors,and20% show familial aggregation in familial form.This type of thoracic aortic aneurysm is called familial thoracic aortic aneurysm(FTAAD),FTAAD difficult to diagnose according to clinical characteristics to use gene sequencing to identify,for the lack of effective,low-cost detection FTAAD gene mutation method,the group developed the IMPATT(Integrated Mutation Profiling of Actionable TAAD Targets,based on high throughput sequencing technology of familial thoracic aortic aneurysm and dissection molecular diagnostic method and application)kit,the evaluation of IMPATT,in order to realize the accurate diagnosis of thoracic aortic aneurysm and dissection.Methods: In this study,135 individuals who met the inclusion and exclusion criteria of thoracic aortic aneurysm / dissection patients at the First Affiliated Hospital of Gannan Medical University from July 2020 to December 2021 were selected for inclusion in the analysis,and the clinical data of the patients were collected,including gender,age,disease history,surgical history,family history,smoking history,drinking history,hypertension history,diabetes mellitus history,blood pressure,body mass index(BMI),upper / lower body length,arm span / height,Glu,TC,TG LDL,HDL,Apo A1,Apo B,UA,D dimer,CRP,CK,CK-MB and the results of CTA + work-up of thoracoabdominal aorta.DNA samples were extracted from peripheral venous blood samples of study subjects and sent to Riokang Chen Bio Technology Co.,Ltd.,Shenzhen,China after the DNA samples were qualified for sequencing using the IMPATT method,which employs exon sequencing of 12 genes involved in FTAAD related ACTA2、COL3A1、FBN1、MYH11、SMAD3、TGFB2、TGFB3、TGFBR1、TGFBR2、MYLK、LOX、PRKG1.Pathogenicity analysis of variants after return of results followed ACMG(American College of medical genetics)guidelines for monogenic disease interpretation to assign each variant classification: Pathogenic(P),Likely pathogenic(LP),Uncertain significance(UVS),Likely benign(LB),benign(B)for variant pathogenicity interpretation,The pathogenic and suspected pathogenic sites detected in the results were tested by Sanger sequencing,and the analysis results were compared.In which 20 cases are less than 50 years old,carrying mutations of TAAD patients extracted DNA samples,sent to Riokang Chen Bio Technology Co.,Ltd.,Shenzhen,China.WES sequencing,the results returned after statistical WES sequencing method after filtering effective data quantity,efficiency percentage,base error rate,GC,Phred score(base quality fraction),etc.,and compare WES sequencing and IMPATT sequencing method in FTAAD related gene sequencing depth and sequencing coverage.Results:1.Of the 135 TAAD patients tested by the IMPATT method,the results showed that 79 of these TAAD patients(58.5%)carried missense mutations.The overall frequency of P / LP variants was 4.4%(6/135),one familial TAAD and five sporadic TAAD carried pathogenic or likely pathogenic(P/LP)variants in four pathogenic genes,and pathogenic or likely pathogenic(P/LP)variants were confirmed by Sanger sequencing.2.The IMPATT method was tested and WES at the same time in 20 patients,and the results showed that the IMPATT method had better sequencing depth than WES,and the sequencing coverage was consistent with the ways of WES.Conclusion:1.The detection rate of TAAD patients was 4.4% using the IMPATT method,which can be used for genetic diagnosis of FTAAD.2.The IMPATT method outperforms WES methods in sequencing depth and is consistent with WES methods in sequencing coverage.3.The IMPATT method can be used to identify FTAAD for genetic screening and improve the diagnostic yield of FTAAD to assist clinical precise diagnosis of diseases as well as treatment.