Study on SNP Genotyping of Degraded DNA by Fluorescence-labeled Multiplex LDR-PCR Amplification / 中国医科大学学报

Objective In this study,a multiplex PCR amplification system was constructed based on fluorescent labeling PCR and LDR,to provide a new strategy for analyzing severely degraded DNA.Methods Eight SNP loci (rs10802248,rs10516197,rs10488372,rs2278945,rs4757318,rs4887255,rs4889002,and rs9304473) were selected.Their LDR probes and PCR primers of linked products were designed and synthesized.Ligase detection reaction,PCR amplification,and capillary gel electrophoresis (CEG) were performed to establish the multiplex LDR-PCR amplification system.Results The genotypes of these 8 loci were obtained simultaneously by the fluorescence-labeled multiplex LDR-PCR amplification method.The loci profiles obtained by fluorescence-labeled multiplex LDR-PCR amplification were in accordance with those obtained by direct sequencing of the polymorphic regions in samples from all individuals.By fluorescence-labeled multiplex LDR-PCR amplification,the 8 SNP loci were efficiently amplified from the severely degraded FFPET DNA.Conclusion Eight SNP loci results could be obtained simultaneously by using the multiplex LDR-PCR amplification system,which is a simple,efficient,and practical SNP genotyping method with accurate and reliable results for highly degraded samples.

Rapid detection of beta-thalassemia by LDR-ULP combined with real-time PCR / 中华检验医学杂志

Objective To establish a new method for rapid detection of β-thalassemia by investigating six clinical common mutation types.Methods Fifty cases of clinical wild-type samples and 42 cases ofβ-thalassemia samples were collected, and β-globin gene was amplified by PCR.Uniform ligation probe ( ULP) specific probes were designed for hybridization reaction to increase the reaction specificity and real-time PCR was performed to increase the sensitivity.After that, PCR products were verified by agarose electrophoresis.After examining the specificity and sensitivity, Kappa test between LDR-ULP method and reverse dot blot( RDB) method was conducted.Results Hybridization efficiency was improved 2.53 times by LDR-ULP hybridization.Each mutant type showed a significant amplification curve, whereas the wild-type had no significant curve within 40 cycles.The limit of determination of this method was 5 pg.The results of 92 cases of peripheral blood samples detected by the method of LDR-ULP and RDB were completely consistent.Conclusion In this study, a simple, inexpensive, rapid new method to detect β-thalassemia were established.