Detection And Bioinformatics Analysis Of Osteogenesis Imperfecta Gene Mutation

Objective:In order to explore the relationship between OI gene mutations and clinical phenotypes by detecting disease-causing gene mutations in diseased individuals in this study and conducting bioinformatics analysis of the mutation sites.Methods:Approved by the Ethics Committee of the Affiliated Hospital of North sichuan medical college,and wih the informed consent of OI patients and their parents,peripheral blood samples of patients and their parents were collected,genomic DNA of whole blood was extracted.Exon chips and high-throughput sequencing were used to detect mutation sites in skeletal&muscular development disorder genes including COL1A1 and COL1A2 in patient samples,and Sanger sequencing was performed to verify the mutation sites.Genomic DNA from peripheral blood of 100 normal people was collected and extracted as a control sample,and the target gene sequence was amplified by PCR.The product was sequenced to verify whether the mutation was present in the normal population.Finally,bioinformatics software was used to analyze the pathogenic risk of mutation sites.Results:(1)The genetic test results showed that there was a c.982G>A mutation in exon 19 of the COL1A2 gene in this OI patient.The mutation site was not detected in the parental peripheral blood samples,suggesting that it may be a new mutation.This site has been reported in the type I collagen mutation database,but it was first discovered in Sichuan.(2)This mutation was not detected in normal human control samples,excluding the general polymorphic variation.(4)Bioinformatics software analyzed that the glycine at the mutation site was highly conserved.PolyPhen and SIFT predicted that the mutation was a missense mutation;HSF3 and Mutationtaster predicted that splice abnormalities might exist after the mutation;Pfam predicted that the protein domain would change after the mutation.Conclusion:(1)The COL1A2 gene c.982G>A(p.G328S)mutation may be the cause of the disease in this patient with OI.(2)Gene mutations may cause the structural changes of the ?2 chain of type I collagen,affect the formation of collagen triple helix regions,change the collagen structure,and eventually lead to OI.(3)The COL1A2 gene c.982G>A(p.G328S)mutation expands the mutation lineage of OI in Sichuan,and is helpful for genetic counseling and prenatal diagnosis in this region.