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PubMed1997

Influence of viral genotype and level of viremia on the severity of liver injury and the response to interferon therapy in Spanish patients with chronic C infection.

BACKGROUND: We wanted to investigate the influence of viral genotype on the severity of liver injury and response to interferon and whether the level of viremia differs in accordance with genotype, severity of liver disease, and response to interferon in patients with hepatitis C virus (HCV) infection. METHODS: We studied 118 patients with HCV-related liver disease. HCV genotypes were determined with a line probe assay, and serum HCV RNA levels with a competitive reverse transcription polymerase chain reaction assay. RESULTS: HCV type 1b was the most prevalent genotype (88%). It was present in 100% of cirrhotic patients, with or without hepatocellular carcinoma (HCC), but only in 78% of patients with chronic hepatitis (P < 0.001). The response to interferon was better in patients infected with non-1b HCV genotypes (P = 0.002). In a multivariate analysis non-1b HCV genotypes and a low hepatic fibrosis correlated with a favorable response to interferon. Among patients with chronic hepatitis those infected with HCV type 1b were older (P < 0.001), and age was the only independent factor associated with HCV type 1b. Viremia levels differed neither between genotypes nor in response to interferon and was significantly lower in patients with cirrhosis and HCC. CONCLUSIONS: HCV 1b was associated with more severe liver disease and a worse response to interferon therapy. Non-1b genotypes and a lower liver fibrosis were the only independent predictors of a favorable response to interferon. Levels of HCV viremia differed neither among different genotypes nor in response to interferon and decreased with advanced liver disease.

Aged↗
PubMed1997

Distribution of hepatitis C virus genotypes in Slovenia.

To determine the prevalence of HCV genotypes in Slovenia, 203 subjects infected with hepatitis C virus (HCV) were studied using the Inno-Lipa HCV II assay (Innogenetics, Belgium). Of 21 patients infected by blood transfusion 19% had HCV subtype 1a, 81% had subtype 1b, and none of them was infected with genotype 3. In chronic hepatitis C patients infected by unknown cause subtype 1b was the most prevalent (54.4%), followed by subtype 1a (24.6%), genotype 3 (15.8%) and genotype 2 (5.2%). Genotype 3 (45.9%) and subtype 1a (43.2%) predominated among 74 intravenous drug users. In 37 haemodialysis patients genotypes 1 and 2 were almost equally frequent (40.5% and 37.8%, respectively), followed by genotype 3 (21.6%). Significant differences in HCV genotype distribution among distinct epidemiological groups observed in Slovenia indicate a close relationship between certain HCV genotypes and particular routes of viral transmission.

Chi-Square Distribution↗
PubMed1994

Determination of effects of milk protein genotype on production traits of Israeli Holsteins.

Genotypes of 112 Israeli Holstein sires were determined for beta-lactoglobulin and kappa-casein by restriction fragment length polymorphism analysis of amplified DNA. Frequencies of the A alleles were .89 and .52 for kappa-casein and beta-lactoglobulin, respectively. Genotype frequencies were in accordance with Hardy-Weinberg equilibrium. Two models were used to test the effect of these loci on production of milk, fat, and protein and on fat and protein percentages. The dependent variable in the first model was production of 84,593 daughters of 110 genotyped sires, and the independent variables were herd-year-season, sire genotype for beta-lactoglobulin and kappa-casein, the interaction of the two loci, and sire nested within genotype. In the second model, the dependent variable was individual animal model genetic evaluations of 111 sires for production traits, and milk protein genotypes were the independent variables. The only significant effect of genotype with both models was the interaction of the two loci on fat percentage. When sires, rather than cows, were genotyped, the contrasted groups differed by only one-half of the genotype effect, but the residual variance was reduced.

Alleles↗
PubMed2005

Hepatitis B virus genotype C prevails among chronic carriers of the virus in Korea.

Hepatitis B virus (HBV) is one of the major causative agents of chronic liver diseases in Korea. HBV has been classified into 8 genotypes by a divergence of >8% in the entire genomic sequence, and have distinct geographic distributions. There are limited data on the relevance between HBV genotypes and clinical outcomes in Korea. To investigate the clinical feature relating to HBV genotype in Korea, a total 120 serum samples with HBsAg (65 from Seoul and 55 from the other city in Korea) were obtained from each 30 chronic HBV carriers with asymptomatic carrier (ASC), chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). HBV genotype was determined by either enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies against genotype-specific epitopes in the preS2-region or the direct sequencing of small S gene. HBV genotypes were determined in 105 (87.5%) of 120 samples. HBV genotype C was identified in all HBV carriers with ASC, CH, LC, and HCC. Genotypes A, B, D, E, F and G were not detected in any of them. Genotype C HBV prevails predominantly among chronic carriers of the virus in Korea, irrespective of their clinical stages of liver disease and geographic origin.

Carrier State↗
PubMed2004

Hepatitis B virus genotypes, phylogeny and occult infection in a region with a high incidence of hepatocellular carcinoma in China.

AIM: To determine the genotypes and phylogeny of hepatitis B viruses (HBVs) in asymptomatic HBV carriers, and the prevalence of occult HBV infection in Long An County, Guangxi Zhuang Autonomous Region, an area with a high incidence of hepatocellular carcinoma. METHODS: A nested polymerase chain reaction (nPCR) was used for detection of HBV DNA in serum samples from 36 blood donors with asympmatic HBV infection, and in serum samples from 52 HBsAg negative family members of the children who did not receive hepatitis B vaccination in Long An County. PCR products were sequenced, and the genotype of each HBV sequence was determined by comparison with sequences of known genotypes in the GenBank and EMBL nucleotide databases using the BLAST programme. Phylogenetic trees were constructed by the quartet maximum likelihood analysis using the TreePuzzle software. RESULTS: Twenty (55.56%) of 36 HBV asymptomatic carriers were positive for HBV DNA. They were all genotype C by comparison with sequences of known genotypes in the GenBank and EMBL nucleotide databases. The full-length HBV DNA sequence isolated from the sample No. 624 contained 3 215 bases. No interesting mutations were found in this isolate. The homology analysis showed that this strain was closer to the Vietnamese HBV genotype C strain, with a homology of 97%, compared its relation to the same genotype of HBV isolated in Shanghai. Six (11.5%) of the 52 HBsAg negative family members were positive for HBV DNA. A point mutation was found in the sample No. 37, resulting in the substitution of amino acid glycine to arginine in the "a" determinant. Other samples with positive HBV DNA did not have any unusual amino acid substitutions in or around the "a" determinant, and were attributed to the wild-type HBV. CONCLUSION: The HBVs isolated from asymptomatic carriers of Long An County were all identified as genotype C, and the prevalence of occult HBV infection in the population of the county is as high as 11.5%. It is suggested that genotype C and persistent occult HBV infection may play an important role in the development of HCC in the county.

Adolescent↗
PubMed2005

New combination test for hepatitis C virus genotype and viral load determination using Amplicor GT HCV MONITOR test v2.0.

AIM: To develop a new sensitive and inexpensive hepatitis C virus (HCV) combination test (HCV Guideline test) that enables the determination of HCV genotypes 1, 2 and 3, and simultaneous determination of HCV viral load using commercial Amplicor GT HCV MONITOR test v2.0 (microwell version). METHODS: The HCV Guideline test used the PCR product generated in commercial Amplicor GT HCV Monitor test v2.0 for viral load measurement using microwell plate version of Amplicor HCV Monitor and also captured on separate plates containing capture probes and competitive oligonucleotide probes specific for HCV genotypes 1, 2 and 3, The HCV genotype was subsequently determined using the biotin-labeled PCR product and five biotin-labeled HCV-specific probes. RESULTS: The sensitivity of the HCV Guideline test was 0.5 KIU/mL. Specificity of the HCV Guideline test was confirmed by direct sequencing of HCV core region and molecular evolutionary analyses based on a panel of 31 samples. The comparison of the HCV Guideline test and an in-house HCV core genotyping assay using 252 samples from chronic hepatitis C patients indicated concordant results for 97.2% of samples (59.5% genotype 1, 33.7% genotype 2, 6.0% genotype 3, and 0.8% mixed genotypes). Similarly, the HCV Guideline test showed concordance with a serological test, and the serological test failed to assign any serotype in 12.7% of the samples, indicating a better sensitivity of the HCV Guideline test. CONCLUSION: Clinically, both viral load and genotypes (1, 2 and 3) have been found to be major predictors of antiviral therapy outcome regarding chronic hepatitis C based on guidelines and they are, in normal circumstances, performed as separate stand-alone assays. The HCV Guideline test is a useful method for screening large cohorts in a routine clinical setting for determining the treatment regimen and for predicting the outcome of antiviral therapy of chronic hepatitis C.

Evolution, Molecular↗
PubMed2007

Hepatitis C virus genotypes in Serbia and Montenegro: the prevalence and clinical significance.

AIM: To investigate the prevalence of hepatitis C virus (HCV) genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection. METHODS: A total of 164 patients was investigated. Complete history, route of infection, assessment of alcohol consumption, an abdominal ultrasound, standard biochemical tests and liver biopsy were done. Gene sequencing of 5' NTR type-specific PCR or commercial kits was performed for HCV genotyping and subtyping. The SPSS for Windows (version 10.0) was used for univariate regression analysis with further multivariate analysis. RESULTS: The genotypes 1, 2, 3, 4, 1b3a and 1b4 were present in 57.9%, 3.7%, 23.2%, 6.7%, 6.7% and 1.8% of the patients, respectively. The genotype 1 (mainly the subtype 1b) was found to be independent of age in subjects older than 40 years, high viral load, more severe necro-inflammatory activity, advanced stage of fibrosis, and absence of intravenous drug abuse. The genotype 3a was associated with intravenous drug abuse and the age below 40. Multivariate analysis demonstrated age over 40 and intravenous drug abuse as the positive predictive factors for the genotypes 1b and 3a, respectively. CONCLUSION: In Serbia and Montenegro, the genotypes 1b and 3a predominate in patients with chronic HCV infection. The subtype 1b is characteristic of older patients, while the genotype 3a is common in drug abusers. Association of the subtype 1b with advanced liver disease, higher viral load and histological activity suggests earlier infection with this genotype and eventually its increased pathogenicity.

Adolescent↗
PubMed2003

Follow up of infection of chacma baboons with inoculum containing A and non-A genotypes of hepatitis B virus.

AIM: To determine whether one genotype (A or non-A genotypes of HBV) predominated over the other during the course of HBV infection. METHODS: Four baboons were inoculated with HBV. DNA was extracted from serum obtained at monthly intervals post-inoculation for 52 weeks and HBV DNA was amplified using primers specific for the core region containing an insert characteristic of genotype A (nt 2 354-2 359, numbering from the EcoRI site). The amplicons were cloned into PCR-Script(TM) and a minimum of 15 clones per time point were sequenced in both directions. RESULTS: Both genotypes persisted for the entire follow-up period of 52 weeks. Genotype non-A predominated in two baboons and genotype A in one baboon. Neither genotype predominated in the fourth baboon, as shown at a 5 % level of testing. CONCLUSION: No conclusions concerning the dominance of either genotype or the natural progression or replication rates of HBV could be drawn because the pattern of the genotypes found may have been caused by sampling fluctuations at the time of DNA extraction and cloning as a result of the very low viral loads in the baboon sera.

Animals↗
PubMed1997

Humoral response to defined Plasmodium falciparum antigens in cerebral and uncomplicated malaria and their relationship to parasite genotype.

The prevalence and concentration of IgG antibodies to defined Plasmodium falciparum antigens were assessed in serum samples of 97 children with cerebral malaria and 146 children with uncomplicated malaria. The antigens used included the schizont extract, ring-infected erythrocyte surface antigen, the C-terminal region of merozoite surface antigen-1 (MSA-1) (BVp42), and three recombinant proteins of MSA-2 (FC27, 3D7, and d3D7). Parasite isolates from 24 children with cerebral malaria and 22 children with uncomplicated malaria were genotyped for MSA-1 and MSA-2. The distribution of parasite genotypes belonging to the different allelic families was similar in both the cerebral and uncomplicated malaria groups. There were higher antibody levels to antigens derived from the infecting parasite genotype than to heterologous genotypes, but this difference was only statistically significant for antibody against the d3D7 antigen among children infected with the 3D7 parasite genotype (mean log = 4.72 versus 3.45 antibody units [AU]; P = 0.029). Those who died were more likely to be infected with the FC27 genotype and had lower antibody levels to MSA-2 of the 3D7 type than had cerebral malaria patients who survived (mean log = 2.94 versus 3.79 AU; P = 0.049). Antibodies against parasites of the 3D7 genotype are associated with a better prognosis among children with cerebral malaria partly because these children are more likely to be infected with parasites of this genotype rather than the FC27 genotype, which appears to be more virulent.

Acute Disease↗
PubMed1998

Hepatitis C virus genotypes and hepatitis G virus in hemodialysis patients from Syria: identification of two novel hepatitis C virus subtypes.

High prevalence of hepatitis C (HCV) and hepatitis G (HGV) viruses has been reported among hemodialysis patients with substantial heterogeneity of HCV genotypes throughout the world. We studied HCV prevalence, clinical significance, genotype distribution, and HGV coinfection in hemodialysis patients from Syria. Ninety (75%) of 120 screened patients were HCV antibody positive. Forty-nine (87.5%) of 56 HCV antibody-positive patients had HCV RNA detected by the polymerase chain reaction. The HCV genotyping was possible in 37 of 49 patients (76%). The HCV genotype distribution was genotype 1a, seven (19%); genotype 1b, 10 (27%); genotype 4a, 11 (30%); unmatched sequences, nine (24%). Phylogenetic analysis of unmatched sequences indicated that they represent two distinct and novel subtypes of HCV genotype 4. Hepatitis G virus RNA was detected in 29 (59%) of the HCV RNA-positive patients. No differences were identified between patients infected with HCV alone and those coinfected with HGV. These data demonstrate that HCV infection is common in this population with a genotype distribution predominantly made up of types 1 and 4. Coinfection with HGV had no effect on the outcome of HCV infection.

Adolescent↗
PubMed1999

Genotypes of N-acetyltransferase-2 and risk of bladder cancer: a case-control study.

PURPOSE: This study was conducted to examine whether certain slow N-acetylation genotypes could be risk factors for bladder cancer, and the possible association between specific genotypes and the severity of the disease at first diagnosis. MATERIALS AND METHODS: This case-control study included 89 patients with transitional cell bladder cancer (diagnosed over a period of 21 months) and 147 controls. N-acetyltransferase-2 (NAT-2) genotypes were identified by allele specific polymerase chain reaction (PCR) on peripheral blood DNA samples. The x2 test was used for statistical evaluation to compare the differences observed between patients and controls and the different genotypes with tumor grading and local staging at presentation. Relative, attributable and population attributable risks were estimated for the genotypes found to present a significantly increased frequency for bladder cancer. RESULTS: A statistically significant difference in the frequency of genotypes was found between the two groups. The patient group had the higher frequency of slow acetylation genotypes (p = 0.0016). Among slow acetylators, homozygotes 341C/341C and compound heterozygotes 341C/857A had the most excessive risk for bladder cancer (p = 0.0041 and 0.0031, respectively). The 341C/341C genotype was found to be associated with more aggressive disease, in terms of tumor grading at presentation (p <0.05). CONCLUSIONS: According to our data, slow acetylators with 341C/341C and 341C/857A genotypes carry a substantially higher odds ratio (3.73 and 12.46, respectively) for bladder carcinogenesis. Additionally, among the slow acetylators, 341C/341C homozygotes are likely to have a higher risk for more aggressive disease.

Adult↗
PubMed1999

[Genotyping of HCV isolates from different populations in Shanghai by using second generation line probe assay].

OBJECTIVE: To investigate the distribution and frequency of various genotypes in different populations in Shanghai. METHODS: 109 HCV isolates by using RT-nested PCR including 81 from patients with hepatitis C (PHCs), 7 from blood donors (BDs) and 21 from intravenous drug abusers (IVDAs) were genotyped by using recently improved second generation line probe assay (INNO-LIPA HCV II innogenetics N.V.Belgium). RESULTS: Among 81 HCV isolates from PHCs, there were 71 (87.6%) genotype 1b, 4(4.9%)2a, 2(2.5%)3b, 1(1.2%)6a, 2(2.5%) mixed genotypes (1 for 2a or 2c + 2b + 1, 1 for 1b + 6a) and 1 (1.2%) undeterminable respectively, and among 7 from BDs, there were 5 1b and 2 genotype 2a. But among 21 from IVDAs, there were 8(38.1%) genotype 1a, 5(23.8%)1b, 2(9.5%)2a or 2c, 2(9.5%)3a, 1(4.8%) 3b and 3(14.3%) mixed genotypes (1 for 1a + 2a or 2c, 1 for 1b + 2a or 2c + 6a and 1 for 1a + 1b + 3b) respectively. CONCLUSION: (1) 7 HCV subtypes (1a, 1b, 2a, 2b, 3a, 3b and 6a) belonging to 4 HCV genotypes (1, 2, 3, 6) were present in different populations in Shanghai. Of them, 2b, 3a, 3b and 6a were first found. (2) HCV genotype 1b was most commonly found in PHCs and BDs. 1a and 3a were only found in IVDAs. (3) The fact that more HCV subtypes were found in IVDAs in this city.

Adult↗
PubMed1999

Genotyping of measles virus isolates from central Europe and Russia.

Sequence analysis of 285 nucleotides located on the variable part of the N gene was undertaken on measles virus (MV) samples collected from acutely infected patients in Germany, the Czech Republic, Denmark, Poland, and Russia. Two distinct genotypes (C2 and D6) have circulated in Germany between 1993 and 1996. Isolates of genotype C2 were related to strains reported in Germany before 1993. This genotype was also found in the Czech Republic in 1992 and in Denmark in 1997. The occurrence of genotype D6 in Germany is described below for the first time. In 1998, this genotype was identified in Poland. Genotypes C2 and D6 were also reported in Spain and in the United Kingdom between 1992 and 1996. Therefore, it is concluded that these genotypes are widely distributed over Europe. The analysis of the isolates from Russia revealed that genotype A was present in 1988 in the European part of the country and in 1996 in Siberia. An isolate identified in 1997 in Siberia belonged to genotype D6, which had never been found previously in Russia. We also analysed MV obtained from a case of subacute sclerosing panencephalitis (SSPE) in 1995 in Turkey. A comparison of this sequence with published sequences implied that this SSPE case was associated with a new genetic lineage of MV.

Base Sequence↗
PubMed1999

Role of polymorphic GSTM1 and GSTT1 genotypes on NNK-induced genotoxicity.

Polymorphisms in chemical metabolizing genes are known to influence individual susceptibility to environmental cancer. We investigated the role of GSTM1 and GSTT1 polymorphisms in modifying the genotoxicity of a tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) using the sister chromatid exchange (SCE), and the tandem-probe fluorescence in situ hybridization chromosome aberration (CA) assays. NNK (0.24, 0.72 or 1.44 mM) induced a significant concentration-dependent increase in the mean number of SCE regardless of genotypes. In comparing the effects between genotypes, significant increase was observed in GSTM1 null cells compared with GSTM1 positive cells only at the low concentration of NNK (0.24 mM). No significant difference was observed between cells with the null and positive GSTT1 genotypes. Using the CA assay, treatment with NNK (0.12, 0.24 or 0.72 mM) induced a significant concentration-dependent increase in the frequency of CA. In addition, cells with the null GSTM1 genotype had significantly increased CA compared with cells with GSTM1 positive genotype at the three concentrations of NNK. Regarding GSTT1 polymorphism, no significant effect was observed between the null and the positive genotypes. Treatment of the cells with 1 mM glutathione monoethyl ester (GSHME) significantly reduced NNK-induced CA in all cells regardless of their genotypes. The effect was clearly more evident in cells with the GSTM1 positive genotype. Therefore, GSHME is protective against NNK-induced CA with more dominant effect in cells with the GSTM1 positive genotype. Our study indicates that GSTM1 may influence NNK-induced genotoxicity and subsequent tobacco-related health effects.

Adult↗
PubMed2000

Context-dependent and invariant associations between lipids, lipoproteins, and apolipoproteins and apolipoprotein E genotype.

Variation in apolipoprotein (apo)E genotypes predicts variation in plasma cholesterol and apoB; however, the context-dependent associations between high density lipoprotein (HDL) cholesterol, apoA-I, triglycerides, and lipoprotein[a] (Lp[a]) and this polymorphism remain unsettled. We genotyped 5,025 women and 4,035 men sampled to represent a white general population in the age range 20 to 80+ years (mean ages 58 and 57 years for women and men, respectively). The relative frequencies of the varepsilon22, varepsilon32, varepsilon42, varepsilon33, varepsilon43, and varepsilon44 genotypes were 0.005, 0.127, 0.027, 0.564, 0.251, and 0. 027, respectively. Variations in apoE genotype (in the order listed above) predicted stepwise increases in cholesterol and apoB in both genders (all ANOVAs: P < 0.001), and stepwise decreases in HDL cholesterol and apoA-I in women (both ANOVAs: P < 0.001), but not in men. In both genders varepsilon33 individuals had the lowest levels of nonfasting triglycerides, whereas the highest levels were found in individuals with varepsilon22 and varepsilon44 genotypes (both ANOVAs: P < 0.001). Finally, a stepwise increase in Lp[a] was seen in women (ANOVA: P < 0.001), but not in men. In women, the association between variation in nonfasting triglycerides and Lp[a], and variation in apoE genotypes was mainly seen in those with the highest alcohol consumption, similar to the consumption of most men. Variations in apoE genotype predicted 5% and 11% in women, and 2% and 6% in men, of the total variation in plasma cholesterol and apoB, respectively. Variation in levels of plasma lipoproteins is associated with variation in apoE genotypes in the population at large, with the most pronounced association in women, except for nonfasting triglycerides, for which the association is most pronounced in men.Whereas the associations between variation in plasma cholesterol and apoB and the variation in apoE genotypes seem invariant, the associations with variation in plasma HDL cholesterol, apoA-I, nonfasting triglycerides, and Lp[a] seem context dependent.

Adult↗
PubMed2001

Association of the ADH2 genotypes with skin responses after ethanol exposure in Japanese male university students.

BACKGROUND: A contribution of the alcohol dehydrogenase-2 (ADH2) polymorphism to alcohol sensitivity and alcohol drinking behavior is still controversial. In this study, we examined the effects of the ADH2 genotypes on skin reactions to ethanol and habitual alcohol intake among Japanese male university students, controlling for the effects of the low Km aldehyde dehydrogenase (ALDH2) genotype, as an extension of our previous study. METHODS: The study subjects were 357 Japanese male students [average age (mean +/- SD) was 23.7 +/- 3.0 years] in a medical university. The subjects completed a questionnaire regarding self-reported alcohol-associated symptoms and alcohol-drinking behavior. The ADH2 and ALDH2 genotypes were determined through digestion of polymerase chain reaction products by restriction enzymes. All subjects participated in the ethanol patch test. We observed skin responses at 0, 5, 15, and 20 min after removal of the tape. RESULTS: Among the ALDH2*1/*1 genotypes, only some subjects with ADH2*1/*2 or ADH2*2/*2 exhibited a positive response, which increased with increasing time after the removal. However, none of comparisons between the different ADH2 genotypes reached statistical significance. Among the ALDH2*1/*2 genotypes, those with ADH2*1/*2 or ADH2*2/*2 showed a significant increase in response with increasing time after the removal and revealed a significantly higher positivity rate at 15 min than those with ADH2*1/*1. In those with the ALDH2*1/*2 genotype, the positive rate of facial flushing with one glass of beer was higher in those with ADH2*1/*2 and ADH2*2/*2 than those with ADH2*1/*1, although this was not significant. However, the ADH2 genotype did not seem to influence drinking frequency or amounts of alcohol intake in each ALDH2 genotype. CONCLUSIONS: This study finds further evidence for a contribution of the ADH2 polymorphism to skin reactions after either local or systemic ethanol exposure in Asian people. However, the effects of the ADH2 polymorphism may be mild because this polymorphism does not seem to influence alcohol drinking behavior in these study subjects.

Adult↗
PubMed2001

HCV genotype analysis in HCV-HIV-co-infected Puerto Ricans who are injecting drug users: undetermined and mixed infections.

Direct percutaneous exposure is the main route of HCV transmission. In Puerto Rico half of people infected with HIV use illicit drugs. The effects of HCV in the course of HIV infection and vice versa have been extensively studied, but remain highly controversial. This may be due to HCV genetic heterogeneity. Therefore, a complex classification into genotypes has emerged that prompted us to determined how this impacts a population of intravenous drug users (IDUs) co-infected with HIV-1. Using Inno-LiPa II technique, we analyzed samples from 171 HCV-HIV-1-co-infected IDUs and 375 from a general HCV population of unknown HIV or source of infection status. Similar HCV genotype distribution was detected in these populations. HCV genotype 1a was the most frequently in IDUs-co-infected with HIV-1, followed by 1b and 3a. Twenty mixed infections and 5 undetermined genotypes were reported. A reduced HCV viral load was observed in HIV-1 positives with wasting syndrome. Individuals with a high HIV-1 viral load presented a low HCV viral load. There were no correlation between HCV genotypes and AIDS-related event. Patients with genotype 1b showed a higher HCV viral load. Males presented higher HCV viral load than females. Females were predominantly affected by genotype 1a, and men by 1a and 1b. Neither the HCV viral load nor the frequency of genotypes were influenced by the antiretroviral modality. The importance of continuous genotype monitoring is stressed.

Adult↗
PubMed2002

[Classification of genotyping hepatitis B virus with multiplex PCR].

OBJECTIVE: To establish a simple and practicable method to identify the different genotypes of hepatitis B virus (HBV). METHODS: Based on the alignment of 114 complete nucleotide sequence for HBV DNA of different genotypes, the specific sequence of each genotype was found. Six primer sets were designed for each of the six genotypes according to the genotype-specific sequence, and used separately for PCR. The genotype of HBV was identified according to the positive result of PCR. Three primer sets for B, C and D genotypes were added into a single tube for PCR reaction, and HBV was genotyped according to the length of the amplified DNA. RESULTS: There was no difference in the genotyping result of PCR by single or multiplex primers, which was identical to the PCR-RFLP method. CONCLUSIONS: This multiplex PCR method is simple, precise, sensitive, and easy to use.

DNA Primers↗