Impact of IL28B gene polymorphisms rs8099917 and rs12980275 on response to pegylated interferon-α/ribavirin therapy in chronic hepatitis C genotype 4 patients

Host genetic factors may predict the outcome and treatment response in hepatitis C virus（HCV）infection.One of these factors is the single nucleotide polymorphisms of the interleukin 28B（IL28B）gene.We sought to evaluate the outcome of pegylated interferon and ribavirin therapy in association with IL-28B rs8099917 and rsl2980275 in patients infected with HCV genotype 4.A total of 180 patients with chronic hepatitis C were selected from Egyptians who have received combined therapy with pegylated interferon and ribavirin for 6 months and their response was evaluated after follow-up at 0,6,12,24 and 48 weeks from the beginning of the therapy.Blood samples were collected from responders and non-responders.Genomic DNA was extracted from whole blood and genotyping was carried out by polymerase chain reaction and restriction fragment length polymorphism（PCR-RFLP）.Our results showed that TT genotype of rs8099917 was associated with higher sustained viral response（SVR）rates and G allele represented a risk factor for failure of response（OR=3.7,CI=1.8：7.64）while rs12980275 was not significantly associated with SVR in genotype 4 Egyptian patients.The determination of 1L-28B SNPs may be useful in enhancing correct prediction of SVR achievement in treating this group of genotype 4 patients.

CYP2C19 Polymorphism and Clinical Outcomes among Patients of Different Races Treated with Clopidogrel:A Systematic Review and Meta-Analysis

Several studies have investigated the association between CYP2C19 polymorphism and clinical outcomes of patients treated with clopidogrel, but few have noticed the difference in association between Westerners and Asians. We searched MEDLINE, EMBASE and Cochrane Library database and conducted a systematic review and meta-analysis. Thirty-six studies involving 44 655 patients with coronary artery disease（CAD） treated with clopidogrel were included, of which more than 68% had undergone percutaneous coronary intervention（PCI）. The primary outcome of our interest was the recurrence of major adverse cardiovascular events（MACE） in those CAD patients. Firstly, we found that the distribution of reduced-function CYP2C19 allele varied between Westerners and Asians. Among Asians, 1 and 2 reduced-function CYP2C19 mutant allele carriers accounted for 42.5% and 10%, respectively. While among Westerners, 1 and 2 reduced-function CYP2C19 mutant allele carriers accounted for 25.5% and 2.4%, respectively. Secondly, the impact of CYP2C19 polymorphism on clinical outcomes of patients treated with clopidogrel varied with races. Among Asians, only 2 reduced-function CYP2C19 mutant allele carriers had the reduced effect of clopidogrel. And the reduced effect was significant only after the 30 th day of treatment. While among Westerners, both 1 and 2 reduced-function CYP2C19 allele carriers had the reduced effect, and it mainly occurred within the first 30 days. Thirdly, the safety of clopidogrel was almost the same among races. Reduced-function allele non-carriers had higher risk for total bleeding but did not have higher risk for major bleeding. It is suggested that CYP2C19 polymorphism affects the efficacy of clopidogrel differently among Westerners and Asians.

Severe acute respiratory syndrome-associated coronavirus genotype and its characterization

Objective To study the severe acute respiratory syndrome (SARS) -associated coronavirus genotype and its characteristics.Methods A SARS-associated coronavirus isolate named ZJ01 was obtained from throat swab samples taken from a patient in Hangzhou, Zhejing province. The complete genome sequence of ZJ01 consisted of 29 715 bp (GenBank accession: AY297028, version; gi: 30910859). Seventeen SARS-associated coronavirus genome sequences in GenBank were compared to analyze the common sequence variations and the probability of co-occurrence of multiple polymorphisms or mutations. Phylogenetic analysis of those sequences was done.Results By bioinformatics processing and analysis, the 5 loci nucleotides at ZJ01 genome were found being T, T, G, T and T, respectively. Compared with other SARS-associated coronavirus genomes in the GenBank database, an A/G mutation was detected besides the other 4 mutation loci (C: G: C: C/T: T: T: T) involved in this genetic signature. Therefore a new definition was put forward according to the 5 mutation loci. SARS-associated coronavirus strains would be grouped into two genotypes (C: G: A: C: C/T: T: G: T: T), and abbreviated as SARS coronavirus C genotype and T genotype. On the basis of this new definition, the ZJ01 isolate belongs to SARS-associated coronavirus T genotype, first discovered and reported in China's Mainland. Phylogenetic analysis of the spike protein gene fragments of these SARS-associated coronavirus strains showed that the GZ01 isolate was phylogenetically distinct from other isolates, and compared with groups F1 and F2 of the T genotype, the isolates of BJ01 and CUHK-W1 were more closely related to the GZ01 isolate. It was interesting to find that two (A/G and C/T) of the five mutation loci occurred in the spike protein gene, which caused changes of Asp to Gly and Thr to He in the protein, respectively.Conclusion Attention should be paid to whether these genotype and mutation patterns are related to the virus' s biological activities, epidemic characteristics and host clinical symptoms.

RHD gene polymorphism among RhD-negative Han Chinese

Objective To evaluate the status of eight RHD specific exons in 131 Han Chinese blood donors who were classified as RhD-negative by serological methods and explore the genomic structure of RHD gene among the Han Chinese. The Rh blood group system has the highest prevalence of polymorphisms among human blood group systems and is clinically significant in transfusion medicine. The Rh antigens are expressed on polypeptides encoded by two highly homologous genes,RHD and RHCE. Recent molecular studies have shown that the RhD-negative trait could be generated by multiple genetic mechanisms and is ethnic group-dependent. Methods The polymerase chain reaction using-sequence specific primers (PCR-SSP) was used to amplify exons 2,3,4,5,6,7,9 and 10 of RHD gene and exons 1,2 and 5 of RHCE gene,as well as intron 4 in each of them.Results The 131 cases of RhD-negative phenotypes consisted of 60 ccee,58 Ccee,5 ccEe,5 CcEe and 3 CCee. Among them,83 with the Rh ccee or ccEe phenotypes (63.4%) lacked the eight RHD exons indicated above,while 26 cases with the Rh Ccee,CCee,CcEe phenotypes (19.9%) had all the RHD exons examined. Twenty-two individuals with the Ccee,CCee,CcEe phenotypes (16.8%) carried at least one RHD exon. The phenotypes of the RhD negative individuals carrying the RHD gene were Rh CC or Cc,but not cc. Conclusions Three classes of RhD-negative polymorphisms among a population of Han Chinese were observed. Antigen association analysis suggested the existence of a novel class of RhD-negative associated haplotype in Han Chinese. This haplotype consisted of a normal RHCE allele and a nonfunctional RHD gene. It may be beneficial to redefine the RhD-negative blood group among Chinese populations upon clarification of the mechanisms of RHD gene expression and RhD antigen immunization.

Super-assembly of integrated gold magnetic assay with loopmediated isothermal amplification for point-of-care testing

With the increasing global threat of various diseases and infections,it is essential to develop a fast,low-cost,and easy-to-use point-of-care testing(POCT)system for inspections at all levels of medical institutions and self-examination at home.In this work,gold magnetic nanoparticles(GMNPs)are used as the key material,and a rapid visual detection method is designed through integrating loop-mediated isothermal amplification(LAMP)and lateral flow assay(LFA)biosensor for detecting a variety of analytes which includes whole blood,buccal swabs,and DNA.It is worth to note that the proposed method does not need DNA extraction.Furthermore,uracil DNA glycosylase(UDG)is employed to eliminate carrier contamination for preventing false positive results.The whole detection process can be finished within 25 min.The accuracy of detection is measured by assessing the polymorphisms of the methylenetetrahydrofolate reductase(MTHFR)C677T.The detection limit of the newly developed extraction-free detection system for MTHFR C677T is 0.16 ng/μL.A preliminary clinical study of the proposed method is carried out by analyzing 600 clinical samples(including 200 whole blood samples,100 buccal swabs,and 300 genomic DNA samples).The results indicate that the proposed method is 100%consistent with the sequencing results which provides a new choice for POCT and shows a broad application prospect in all levels of medical clinics and at home.