Multiplex qPCR for serodetection and serotyping of hepatitis viruses: A brief review

The present review describes the current status of multiplex quantitative real time polymerase chain reaction(q PCR) assays developed and used globally for detection and subtyping of hepatitis viruses in body fluids. Several studies have reported the use of multiplex q PCR for the detection of hepatitis viruses, including hepatitis A virus(HAV), hepatitis B virus(HBV), hepatitis C virus(HCV), hepatitis D virus(HDV), and hepatitis E virus(HEV). In addition, multiplex q PCR has also been developed for genotyping HBV, HCV, and HEV subtypes. Although a single step multiplex q PCR assay for all six hepatitis viruses, i.e., A to G viruses, is not yet reported, it may be available in the near future as the technologies continue to advance. All studies use a conserved region of the viral genome as the basis of amplification and hydrolysis probes as the preferred chemistries for improved detection. Based on a standard plot prepared using varying concentrations of template and the observed threshold cycle value, it is possible to determine the linear dynamic range and to calculate an exact copy number of virus in the specimen. Advantages of multiplex q PCR assay over singleplex or other molecular techniques in samples from patients with co-infection include fast results, low cost, and a single step investigation process.

Progress in genotyping of Chlamydia trachomatis

Objective To review the common genotyping techniques of Chlamydia trachomatis in terms of their principles,characteristics,applications and limitations.Data sources Data used in this review were mainly from English literatures of PubMed database.The search terms were ＂Chlamydia trachomatis＂ and ＂genotyping＂.Meanwhile,data from World Health Organization were also cited.Study selection Original articles and reviews relevant to present review＇s theme were selected.Results Different genotyping techniques were applied on different occasions according to their characteristics,especially in epidemiological studies worldwide,which pushed the study of Chlamydia trachomatis forward greatly.In addition,summaries of some epidemiological studies by genotyping were also included in this work for reference and comparison.Conclusions A clear understanding of common genotyping techniques could be helpful to genotype C.trachomatis more appropriately and effectively.Furthermore,more studies on the association of genotypes of Ch/amydia trachomatis with clinical manifestations should be performed.

Full screening and accurate subtyping of HLA-A＊02 alleles through group-specific amplification and mono-allelic sequencing

HLA-A＊02 is the most prevalent and polymorphic major histocompatibility complex （MHC） allele family in humans. Functional differences have been revealed among subtypes, demanding further subtyping of HLA-A＊02 in basic and clinical settings. However, the fast growing polymorphisms render traditional primeror probe-based typing methods impractical and result in increasing ambiguities in direct sequence-based typing. In this study, we combined group-specific amplification and mono-allelic sequencing to design and validate a simple scheme for the complete screening and accurate subtyping of all 540 reported HLA-A＊02 alleles. This scheme could be performed in routine labs to facilitate studies with an interest in HLA-A＊02.