The Application Of NGS In Patients With Wilson’s Disease And Relationship Between Genotype And Phenotype Of It

Objectives: Wilson’s Disease(WD)is an autosomal recessive monogenic inherited disorder caused by ATP7 B pathogenic variants,characterized by pathological copper hyperaccumulation.It’s particularly important to detect ATP7 B gene mutation for the early diagnosis.Next-generation sequencing(NGS),as known as high-throughput sequencing,is cheaper,faster and more accurate than first-generation sequencing in detecting the mutations.The purpose of this study was to explore the efficiency of NGS on the detection of WD mutations,the correlation between variant types and clinical phenotypes,and to supplement the ATP7 B gene database.Methods: Patients who were diagnosed with Wilson’s disease(WD)and had molecular examinations were recruited from July 2003 to December 2020 at In-patient department or Out-patient department,Department of Infectious Disease,Second Xiangya Hospital,Central South University.Their types of ATP7 B gene variant types and clinical phenotypes,such as age of patients being diagnosed,transaminase,bilirubin,urine copper,serum ceruloplasmin levels,K-F ring and liver copper quantity,were collected and collated.Analyzing advantages of NGS,common types of mutation,new variant types of ATP7 B gene,and the relationship between gene mutations and clinical phenotypes.Results:(1)The detection rate of ATP7 B gene mutation by NGS and Sanger sequencing were 98.59%(275/279)and 94.31%(218/232),respectively.NGS is more efficient than the latter(p<0.05).(2)Of the 529 cases included,no mutation was found in18(3.4%),c.2333G>T was detected in 178(33.6%),which was the most common mutation type.In addition,there were 112 cases of c.2975C>T(21.17%),54 cases of c.3443T>C(10.2%),32 cases of c.2755C>G(6.05%),26 cases of c.3316G>A(4.91%),24 cases of c.3809A>G(4.53%),c.2621C>T(4.35%),22 cases of c.2804C>T(4.16%),and C.3884C>T(4.16%).(3)Several ATP7 B gene mutations were not reported before:c.3041C>G,c.3041T>C,c.3044T>G,c.3993T>G,c.3724T>C.(4)Initial ceruloplasmin levels and age of diagnosis were significantly different among different mutation intensities of R778 L.(5)AST was significantly different among different mutation intensities of P992 L and I1148 T.Conclusion:(1)NGS can detect ATP7 B gene mutations better.(2)There were some correlation between ATP7 B gene mutation type and clinical phenotypes.(3)Presently,the ATP7 B mutation databases are not comprehensive,so that need further study.