title: Development of a novel genotype-specific loop-mediated isothermal amplification technique for Hepatitis B virus genotypes B and C genotyping and quantification.
abstract: BACKGROUND
  There is the need for a rapid, economical method for genotyping Hepatitis B virus (HBV) to support clinical practice.
  
  
  OBJECTIVE
  To develop a novel HBV genotyping process using genotype specific loop mediated isothermal amplification (LAMP).
  
  
  METHODS
  HBV genotypes B and C specific LAMP methods were evaluated using standard panel. A comparative analysis of the LAMP test against Taqman assay using 105 clinical samples, was undertaken to evaluate the quantitation capacity of the method. 111 clinical samples were used to test the clinical applicability of the genotype specific LAMP method. The results were compared with those obtained by real-time PCR based genotyping and sequencing.
  
  
  RESULTS
  Using genotype-specific primers, the LAMP assay correctly identified all predefined genotypes B and C, and no cross-reaction was observed. Real-time format of this assay provides simultaneous identification and quantification of genotypes B and C. The detection sensitivity of the method was found to be 323 and 515 copies/ml for genotypes B and C specific LAMP assay respectively. High correlation (R(2)=0.91) and good agreement between the LAMP method and the real-time PCR test were achieved for HBV quantitation. Samples from 111 HBV-infected patients were genotyped with LAMP, revealing 53% HBV as genotype B, 36% as genotype C, and 12% as mixed genotypes B and C. LAMP method showed coincidence rates of 96.7% with the real-time PCR genotyping results.
  
  
  CONCLUSIONS
  This approach is a promising tool for HBV genotyping and quantitation. It appears to be useful for routine clinical practice even in field investigation.
authors: The Second Clinical Medicine College, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors: Zhejun
authors: Z
authors: Cai
authors: Guoqiang
authors: G
authors: Lou
authors: Ting
authors: T
authors: Cai
authors: Jin
authors: J
authors: Yang
authors: Nanping
authors: N
authors: Wu
mesh_terms: D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D006509:Hepatitis B / Q000175:diagnosis / Q000821:virology*; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D019562:Viral Load / Q000379:methods*
chemical_list: D017931:DNA Primers; D004279:DNA, Viral