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PubMedDate not supplied

Association analysis of genotypic frequencies of matrilin-1 gene in patients with osteoarthritis.

OBJECTIVE: It has been suggested that genotypic variation in the gene which encodes the matrilin-1 (MATN-1) protein may be involved in the development of hip osteoarthritis (OA). We compared genotype frequencies of the MATN-1 gene (1p35) in patients with OA and controls to determine if there is any association between the MATN-1 genotype and OA. METHODS: 73 OA patients and 53 controls from a rheumatology ambulatory center and a university hospital were studied. They were unrelated subjects. Controls were free of clinical OA. OA was defined according to the American College of Rheumatology criteria. The MATN-1 microsatellite in the 3'untranslated region was amplified by PCR. The size of the amplification products was determined by capilar electrophoresis in a DNA Genetic Analizer Genotypic distribution was compared by the chi2 test. RESULTS: We identified 4 alleles according to their basepair (bp) length: A1 = 110 bp; A2 = 108 bp; A3 = 106 bp and A6 = 104 pb. Six genotypes were found, with an observed heterozygosity of 0.48. The most frequent genotype in OA and controls was A1/A1 (43.8% and 43.4%, respectively). No significant difference in genotype distribution was found between OA - even when discriminating by the affected joint - and controls. CONCLUSION: We did not find any difference in the MATN-1 genotype distribution in OA patients and controls. To our knowledge, this would be the first time a MATN-1 allele of 104 bp (A6) has been identified These results do not support a role of the MATN-1 genotypes in the occurrence of clinical OA.

Cartilage Oligomeric Matrix Protein↗
PubMed2002

Technologies for individual genotyping: detection of genetic polymorphisms in drug targets and disease genes.

Genetic variations have been associated with a predisposition to common diseases and individual variations in drug responses. Identification and genotyping a vast number of genetic polymorphisms in large populations are increasingly important for disease gene identification and pharmacogenetics. Commonly used gel electrophoresis-based genotyping methods for known polymorphisms include polymerase chain reaction (PCR) coupled with restriction fragment-length polymorphism analysis, allele-specific amplification, and oligonucleotide ligation assay. Fluorescent dye-based DNA fragmentation has been extensively used for high-throughput microsatellite or short tandem-repeat genotyping. TaqMan and molecular beacon genotyping are commonly used homogeneous solution hybridization technologies. Because of the ease of experimental assay design, single nucleotide polymorphism (SNP) genotyping methods based on single-base extension are in rapid development, such as fluorescence homogenous assays, pyrosequencing and mass spectrometry. Non-PCR based genotyping assays such as Invader trade mark assays are promised to genotype directly from genomic DNA without the requirement of PCR amplification. The DNA microarray is a solid phase genotyping format that is rapidly developing for parallel genotyping of a large number of SNPs simultaneously. Advanced technologies to identify genetic polymorphisms rapidly, accurately, and cost effectively will fundamentally change the practice of medicine by allowing physicians to prescribe medicine based on a patient's genetic make-up.

Alleles↗
PubMed1999

[Study on HCV genotypes in different clinical types of hepatitis C patients in Shenyang area].

OBJECTIVE: To study the distribution of HCV genotypes in different clinical types of hepatitis C in Shenyang area and its clinical significance. METHODS: The HCV genotypes of 84 HC patients of different clinical types were detected by PCR assay with four kinds of type-specific primers. RESULTS: In 84 patients with hepatitis C, the HCV-II and HCV-III genotypes and the II/III mixed genotype were 53.6%, 30.9% and 15.5% respectively. The distribution of HCV genotypes in different HC clinical types was not identical, P < 0.05. In acute hepatitis, in mild, moderate and severe degree of chronic hepatitis, and in liver cirrhosis, the infection rates of genotype II HCV were 55.6%, 36.2%, 75.0%, 85.7% and 88.9% respectively, but that of genotype III were 22.2%, 46.8%, 8.3%, 0% and 11.1% respectively. CONCLUSION: Infection of geno type II HCV was predominant in Shenyang area followed by HCV-III and II/III mixed genotypes. The different genotypes of HCV were related to the severity of hepatitis C.

Adult↗
PubMedDate not supplied

[A new, rapid and robust genotyping method for CYP2C9 and MDR1].

Single nucleotide polymorphisms (SNPs) can significantly affect human phenotypes. Detection of allelic variant carriers has become a major goal for clinical pharmacologists in order to study phenotype-genotype relationships. However, there is a crucial need for rapid, and validated pharmacogenetic tests. The aim of the study was to validate a new fluorescence PCR strategy for cytochrome P450 2C9 (CYP2C9) and multidrug resistance gene (MDR1) genotyping. Results of CYP2C9 and MDR1 genotypes determined with reference techniques were compared to those obtained by allelic discrimination assays employing fluorescent TaqMan probes. Sixteen subjects carrying CYP2C9*2 and CYP2C9*3 allelic variants (heterozygous and homozygous) previously identified by sequencing and 55 subjects previously genotyped for MDR1 exon 26 (C3435T) SNP by conventional PCR-RFLP were genotyped with fluorescent PCR. Fluorescent PCR gave 100 % accuracy with the results obtained with reference genotyping strategies for each of the 3 SNPs. Genotyping results with fluorescent PCR repeated on three consecutive occasions remained constant over time for each of the 3 SNPs. Allelic discrimination assays based on fluorescent PCR gave entire satisfaction for CYP2C9 and MDR1 genotyping. This reliable genotyping strategy can be easily used in clinical practice and should be further developed for additional SNPs identification.

Alleles↗
PubMed2003

[Investigation on cagA/vacA dominant genotypes and the coinfection of Helicobacter pylori isolates from patients in Zhejiang].

OBJECTIVE: To determine cagA/vacA dominant genotypes of Helicobacter pylori in patients suffering from chronic gastritis (CG) or peptic ulcer (PU), and to understand the correlation of different genotype H. pylori infection, coinfection and the gastroduodenal diseases. METHODS: H. pylori strains were isolated from antrum and corpus samples on 42 patients with CG and 36 patients with PU. Polymerase chain reaction was used to detect cagA and the s and m regions of vacA in 156 H. pylori isolates from both antrum and corpus. The distribution of H. pylori genotypes and coinfection in CG and PU was analyzed. RESULTS: Almost all of the isolated H. pylori strains were cagA positive. In region of vacA, only one genotype of signal region (s1a) and four genotypes of the middle region (m1, m2, m1b and m1b-m2) were found. The proportions of s1a/m1, s1a/m2, s1a/m1b, s1a/m1b-m2 and coinfection of multiple H. pylori strains in 78 isolates from antrum samples were 6.4%, 55.1%, 26.9%, 1.3% and 3.8%; and the related proportions of those from corpus samples were 6.4%, 53.8%, 25.6%, 3.8% and 5.1%, respectively. Sixteen (20.5%) patients had multiple H. pylori strains with different cagA and vacA genotypes, and multiple samples were better than single sample taken from one stomach to increase the positive proportion of coinfection. CONCLUSION: cagA(+) s1a/m2 was the dominant genotype of H. pylori in the CG or PU patients followed by cagA(+) s1a/m1b in the Zhejiang area of China. Some of the patients were coinfected with multiple H. pylori strains of different cagA and vacA genotypes. However, there was no significant correlation between the genotypes or mixed infection with multiple strains, CG or PU.

Adolescent↗
PubMed2003

Hepatitis B virus genotypes B and C do not affect the antiviral response to lamivudine.

To date, there have been no studies examining the role of hepatitis B virus (HBV) genotypes on the response to lamivudine therapy and the development of YMDD mutations. The present study aimed at determining any differences in the antiviral response and risk of YMDD mutations between lamivudine-treated patients with HBV genotype B and genotype C. Eighty-two patients receiving lamivudine were recruited. HBV genotypes at baseline and YMDD mutations at week 52 were determined by line probe assays (LiPA). HBV DNA levels were determined by the Cobas Amplicor HBV Monitor Test. Seventeen (20.7%) and sixty-four (78%) patients had single genotypes of B and C, respectively. At both week 24 and 52 there were no differences in the median reduction of HBV DNA levels (median 4 logs drop), the median reduction of alanine aminotransferase (ALT) levels, and the proportion with normalization of ALT [8/8 (100%) vs 26/37 (70.3%), P=0.19] between patients with genotypes B and C. The rate of HBeAg seroconversion [3/17 (17.6%) vs 6/64 (9.4%), P=0.39] and the chance of YMDD mutation development [3/17 (17.6%) vs 12/64 (18.8%), P=1.0] at week 52 were also similar between patients with genotype B and C, respectively. In conclusion, there was no difference in the antiviral response and the rate of development of YMDD mutations in Chinese patients with genotype B and C after 1 year of lamivudine. Determination of HBV genotypes before lamivudine therapy was probably not an important pretreatment investigation to predict antiviral responses in Chinese patients.

Adolescent↗
PubMedDate not supplied

Correlations between hepatitis B virus genotype and cirrhotic or non-cirrhotic hepatoma.

BACKGROUND/AIMS: Hepatoma arising in cirrhotic and non-cirrhotic livers might have different virological and clinical factors in hepatitis B virus carriers. This study was performed to elucidate the correlation between hepatitis B virus genotypes and clinical characteristics of patients with cirrhotic and non-cirrhotic hepatoma. METHODOLOGY: One hundred and fifty-five hepatitis B virus carriers who received hepatic resection for hepatoma were investigated to determine hepatitis B virus genotypes and clinical features. RESULTS: Of 155 patients, 84 were genotype B infection, and 67 genotype C. Compared to genotype C carriers, genotype B analogs had a significantly lower rate of liver cirrhosis (p=0.005), lower hepatitis B e antigen positive rates (p=0.0008), and lower fibrosis scores (p=0.003). In comparison to cirrhotic hepatoma patients, non-cirrhotic counterparts were younger (p=0.041), had a higher platelet count (p<0.001), lower hepatitis B e antigen positive rates (p=0.023), predominantly genotype B (p=0.005), lower inflammation scores (p<0.001). Using multivariate analysis, non-cirrhotic hepatoma was associated with genotype B infection (OR=2.85, 95% CI=1.44-5.64) and younger age (OR=0.967, 95% CI=0.94-0.99) in hepatitis B virus carriers. CONCLUSIONS: Our study suggested that hepatitis B virus genotype B infection might be an important factor for non-cirrhotic hepatoma.

Adult↗
PubMed2003

[Comparison of hepatitis B virus serotype and genotype among HBsAg positive hepatitis B patients in a northern and a southern city of China].

OBJECTIVE: To understand HBV serotypes and genotypes epidemiology in a northern city and a southern city in China. METHODS: Using polymerase chain reaction (PCR) and direct sequencing of HBV DNA PCR products, the serotypes and genotypes of HBV in 530 from HBsAg positive samples. The enrolled patients were from Harbin, a northern city and Lianjiang, a southern city in China. RESULTS: Comparison of the serotypes and genotypes of HBV between Harbin and Lianjiang showed that adrq+ was the most predominant hepatitis B virus serotype in both Harbin and Lianjiang (87.2% and 73.5%,respectively), adw2 was the next (12.0% and 25.7%, respectively); genotype C was the most frequent in Harbin and Lianjiang (87.8% and 73.2%, respectively), and genotype B was the next (12.2% and 26.1%, respectively) only 1 patient was infected by genotype D, and 1 patient was found to be co-infected by genotype B and C in Lianjiang. CONCLUSION: The results suggest that the percentage of HBV serotypes and genotypes between Harbin and Lianjiang was significantly different (P less than 0.001), but the main HBV serotype and genotype of the two cities were similar.

China↗
PubMed2004

[Clinical phenotype genotype correlation in children with hemoglobin H disease in Zhuhai area of China].

OBJECTIVE: Alpha-thalassemia is one of the most common monogene disorders in the world. Most frequently, it is caused by deletions of alpha-globin gene (-alpha or --), and less commonly resulted from the non-deletional mutation (alpha(T)alpha). Hemoglobin H (HbH) disease is the most severe type among survivors of alpha-thalassemia. The clinical presentation of children with the disease was highly heterogeneous. The aim of this study was to investigate the effect of alpha-globin genotypes in the children with HbH disease on predicting the phenotypic severity and to define the factors involved in the disease progress. METHODS: Forty-three children with the disease in Zhuhai area of Guangdong, China were examined by using established techniques to detect genotypes of alpha-globin and to determine all hematological parameters. All detailed clinical data of the cases were recorded. Then clinical and hematological findings, and the correlation with genotypes were evaluated. RESULTS: Six alpha-thalassemia mutations were detected and interacted to produce 5 HbH disease genotypes. Of these genotypes, -alpha(3.7)/--(SEA)(60%), -alpha(4.2)/--(SEA) (19%) and alpha(CS)alpha/--(SEA) (12%) HbH diseases were prevalent in the area. Compared with -alpha(3.7)/--(SEA) HbH disease, significantly lower red blood cell (RBC) count, hemoglobin (Hb), mean corpuscular hemoglobin (MCHC) and HbA(2) (P < 0.05, 0.01, 0.01 and 0.01, respectively), and significantly higher mean corpuscular hemoglobin volume (MCV) and HbH levels (both P < 0.01), and more severe clinical phenotypes were found in the HbH disease with alpha(T)alpha/--(SEA) genotype. While the differences were much more significant when compared with -alpha(3.7)/--(SEA) then compared with -alpha(4.2)/--(SEA) not only in the hematological parameters, but also in the severity of clinical phenotypes. In addition, HbH levels showed anegatively correlation with the RBC count (r = -0.39, P < 0.01). CONCLUSION: The phenotypes of HbH disease may be mainly related to the underlying genotypes. The children with alpha(T)alpha/--(SEA) genotype presented with more severe hematological and clinical phenotypes followed by the -alpha(4.2)/--(SEA) and then -alpha(3.7)/--(SEA) genotypes. But phenotypic severity was not simply related to the degree of alpha-globin deficiency. HbH levels were found to exacerbate anemia. These data might provide comprehensive and very valuable and basic information for the management of HbH disease, genetic counseling and prenatal diagnosis.

Child↗
PubMed2004

[Differential acute mortality among the allozyme genotypes of Oxya chinensis by pesticide avermectin].

The rice grasshopper Oxya chinensis exhibits polymorphic loci at Ldh, Gpi, Pgm and Me. The data of the mean number of alleles per locus (A = 2.8), percentage of polymorphic loci (P = 80.0%), the observed mean heterozygosities (Ho = 0.271 approximately 0.279) and the expected mean heterozygosities (He = 0.305 approximately 0.316) of the species suggest that O. chinensis possesses sufficient genetic diversity. It was hypothesized that the high polymorphisms at Ldh, Gpi, Pgm and Me might make it possible for pesticide avermectin to act as a selective agent through differential lethality among the insect individuals with different genotypes. In this study a total of 855 grasshoppers were injected with avermectin (1.3 x 10(-2) g/g) to obtain a mortality of 54% after 24 hours. The allozyme analysis was then employed to determine the genotypes of Ldh, Gpi, Pgm and Me for both dead and surviving individuals. Contingency table chi2 tests showed that avermectin displayed random lethal effects on the genotypes at the loci of Ldh, Pgm and Me, without correlation between the genotype and mortality. In contrast, at Gpi locus, the grasshopper demonstrated a mortality cline of Gpi-AA (38%), Gpi-AB (51%), Gpi-BB (58%) and Gpi-BC (74%). The significant mortality differences were found among the following genotype pairs: Gpi-AA vs. Gpi-BB, Gpi-AA vs. Gpi-BC and Gpi-AB vs. Gpi-BC. These data implied the Gpi-AA genotype was likely related to the specie's resistance to the pesticide avermectin. It was also noted that the Gpi-A allele was present in the genotypes with low morality,while Gpi-B was present in the genotypes with moderate mortality, and the individuals with Gpi-C allele exhibited the highest mortality. The data obtained in this study suggested that the increasing proportion of Gpi-AA genotype and perhaps Gpi-A allele in a population may be useful as a potential resistant biomarker of O. chinensis to pesticide avermectin.

Alleles↗
PubMedDate not supplied

Role of HBV genotype in predicting response to lamivudine therapy in patients with chronic hepatitis B.

BACKGROUND: Predictors of response of chronic hepatitis B (CHB) to lamivudine therapy need better definition. Whether hepatitis B virus (HBV) genotypes could serve as such a predictor has not been well studied. AIM: To study the association of HBV genotypes with the outcome of lamivudine treatment in patients with CHB. METHODS: Seventy-six patients with CHB (45 HBeAg +ve) received lamivudine 100 mg/day, orally for 12 mo. Infecting HBV genotypes were determined in pre-treatment specimens using restriction fragment length polymorphism. End-of-treatment response (ETR) and sustained viral response (SVR) were defined as undetectable HBV DNA (< 0.5 pg/mL) at 12 and 18 months, respectively. RESULTS: ETR was observed in 26 (34%) and SVR in 11 (14%) patients receiving lamivudine. The pre-treatment characteristics of the responders and non-responders were comparable. Genotypes A and D were observed in 28 (37%) and 48 (63%) patients, respectively. The frequency of genotypes A and D was comparable between responders (28.6% vs. 37.5%) and non-responders (71.4% vs. 62.5%), respectively (p=ns). Of the 26 responders, SVR could be evaluated in 20 subjects; 9 (45%) relapsed and 11 achieved SVR. Patients with genotype D achieved higher SVR rate than genotype A (10 of 48, 28.8% vs. 1 of 28, 3.5% p =0.0359). CONCLUSIONS: Forty-five percent of Indian patients with CHB who achieve ETR relapse, and SVR to lamivudine therapy is achieved in 14%. Patients with genotype D achieve higher SVR rate than with genotype A.

Adult↗
PubMedDate not supplied

Trimodal GSTT1 and GSTM1 genotyping assay by real-time PCR.

The GSTT1 and GSTM1 genes are characterized by the existence of a GST*0 null allele responsible for a lack of enzyme activity, with the respective null genotypes GSTT1*0/0 and GSTM1*0/0. The three resulting genotypes (GSTs*1/1, *1/0 and *0/0) are associated with a trimodal distribution of glutathione-conjugator activity. Previous epidemiological studies have only evaluated the cancer risk associated with the GST null genotype relative to the two GST carrier genotypes (GSTs1*1/1 and *1/0). We developed GSTT1 and GSTM1 TaqMan real-time quantitative PCR assays to discriminate each of the three genotypes, with the albumin gene (ALB) as reference. The mean N(GSTT1*1/1) value was 1.0 (95% confidence interval 0.80-1.20). The mean N(GSTT1*1/0) value was 0.48 (95% CI 0.36-0.60). One (3.4%) of the 29 DNA samples yielded the GSTM1*1/1 genotype (N(GSTM1*1/1) = 1), a frequency in keeping with the Hardy-Weinberg distribution. The mean N(GSTM1*1/0) value was 0.50 (95% CI 0.42-0.58). All GSTT1*0/0 and GSTM1*0/0 samples yielded N(GST) values of 0 (Ct = 40); the frequencies of these genotypes (27.6% and 55.2%, respectively) were in keeping with published data. The GSTT1 and GSTM1 real-time PCR assays described here unambiguously discriminate each of the three existing genotypes which should be valuable for assessing the relative risk of cancer associated with each of the three GST genotypes.

Genotype↗
PubMed2005

[Do left ventricular mass, diameters and long-axis systolic function differ according to angiotensin converting enzyme genotypes?].

OBJECTIVE: Angiotensin converting enzyme (ACE) is a key enzyme in angiotensin II production which causes myocardial hypertrophy and hyperplasia. In this study we aimed to investigate the relation between ACE I/D gene polymorphism and left ventricular mass (LVM), dimensions and systolic functions calculated by mitral annular motion (MAM) in young healthy male subjects. METHODS: Complete echocardiographic examination was performed in 49 male healthy subjects (mean age 22.9+/-2.1 years) consisting of 18 ACE DD, 18 ACE DI and 13 ACE II genotypes. We calculated LVM and mass index (LVMI) by M-Mode echocardiography. The systolic MAM was recorded at 4 sites (septal, lateral, anterior, and posterior) by M-mode echocardiography and the MAM-ejection fraction (EF) was calculated from above four sites. Ejection fraction was also calculated by Simpson's method. RESULTS: There was no significant difference among the three genotypes according to age, body mass index, systolic and diastolic blood pressure and heart rate. Interventricular septum (IVS) and left ventricular posterior wall (LVPW) diastolic thickness, LVM and LVMI were found significantly different among 3 ACE genotypes. Those measurements were higher in DD genotype in comparison to the DI and II genotypes. There was no significant difference among the three genotypes according to EF-MAM and EF by Simpson's method. CONCLUSION: In young healthy male subjects having ACE DD genotype, even though LVM and LVMI were within normal limits, their measurements were found to be higher than in subjects with ACE DI and II genotypes respectively. There was no difference among the three genotypes according to left ventricular systolic functions.

Adult↗
PubMedDate not supplied

[The significance of angiotensin-converting enzyme inhibitors genotype for ACEi response in patients with chronic allograft nephropathy].

Investigations conducted in medical centers worldwide and ours indicate that patients with chronic allograft nephropathy (CAN) will have short kidney graft survival when proteinuria and/or azotemia develop early, during the first post transplantation year. The analysis of published results suggests that angiotensin-converting enzyme (ACE) DD genotype represents unfavorable marker of rapid progression of chronic renal allograft dysfunction (CRAD). Differences of response to ACEi therapy in patients with chronic nephropathy of one's one or transplanted kidney could be explained by ACE genotype variety, where ACE DD is unfavorable genotype. Related factors influencing the ACEi therapy success in patients with particular ACE genotype are highly salt diet, interactions of genotype variety of all renin-angiotensin-aldosterone system (RAS) molecules, i.e. diversity in the ACE, angiotensinogen, AT1 receptor or aldosterone genotype, as well as differences of ACEi responses in patients with glomerular and tubulointerstitial kidney diseases. Retardation of chronic renal failure in patients with ACE DD genotype who developed chronic allograft nephropathy has been obtained with long-term ACEi treatment and restricted salt intake to 50 mmol Na+ per day. We consider that genotype investigation of RAS molecule, primarily of ACE genotype in recipient and kidney donor should be done before high-risk kidney transplantation.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2005

[Study on hepatitis C virus genotyping in Yixing area, Jiangsu province].

OBJECTIVE: To investigate the distribution of hepatitis C virus (HCV) genotypes in Yixing, Jiangsu province. METHODS: Genotypes identification on sera samples were obtained from 158 donors who had already been anti-HCV positive through PCR method with type specific primer designed according to the sequence of 5'non-coding region (5'NCR). 5'NCR was also sequenced and compared with published date. Genotypes distribution was investigated in patients with different sex and clinical types of hepatitis C. RESULTS: Of the total 158 patients, 95 were HCV RNA positive in which 80 patients having genotype 1b (80/95; 84.4%), 5 patients having genotype 2(5/95; 5.3%), 5 patients with 1b/2 mixed genotypes (5/ 95; 5.3%) and another 5 patients whose genotype undetermined. The difference on the distribution of HCV genotypes was significant between female and male patients (P < 0.05) but not in different kinds of hepatitis C patients. CONCLUSION: Type 1b was the predominant HCV genotype in Yixing area.

Base Sequence↗
PubMed2006

[Genotype of wild-type measles viruses circulating in Beijing in 2003].

OBJECTIVE: To investigate genotype of wild-type measles viruses circulated in Beijing in 2003. METHODS: Throat swabs specimens were collected from patients seen during an outbreak of measles and from clinically suspected sporadic measles patients in 2003. Vero/SLAM cell lines recommended by WHO were used to isolate measles virus. Four hundreds and fifty nucleotides of COOH-terminal of nucleoprotein (N) genes were amplified by using PR-PCR. The amplified products were sequenced and the sequences were compared with references viruses from GeneBank. RESULTS: Eight strains of measles viruses were isolated from throat swabs of patients who came from seven districts and counties of Beijing. Sequence analysis of the 450 nucleotides of COOH-terminal of nucleoprotein (N) genes indicated that these 8 strains belonged to H1a genotype. The average genetic distances of these 8 strains to H1a genotype, Chin9322, H1b genotype, Chin9475 and H1c genotype, Chin9427, were 0.004 - 0.011, 0.026 - 0.031 and 0.015 - 0.022, respectively. The average genetic distances of these 8 strains to H1a genotype, Anhui 01 - 1/Anhui 02 - 2, were 0.000 - 0.009 (0 - 5 nucleotide variation). CONCLUSIONS: Major genotypes of wild-type measles viruses circulated in Beijing in 2003 were H1a genotype. The genotypes H1c, H1b and H2 may have disappeared in Beijing.

Child↗
PubMed2006

[Genotyping of hepatitis B virus by restriction enzyme analysis].

Hepatitis B is one of the most common infectious diseases in the world, and 350 million people have been estimated to be chronic hepatitis B virus carriers world-wide. Hepatitis B virus (HBV) has been classified into 8 genotypes (A-H) based on an intergroup divergence of 8% or more in the complete nucleotide sequence. Different genotypes of the hepatitis B virus may influence the clinical outcome of the disease. HBV genotyping method using restriction fragment length polymorphism (RFLP) can reliably identify genotypes. HBV genotyping with S gene sequence is consistent with genetic analysis using the full genomic sequences. The aim of this study was to determine the genotypes of HBV by using restriction fragment length polymorphism (RFLP) method in the region of Elazig. A total of 127 HBV-DNA positive patients (74 male, 53 female) were included in the study. Semi-nested polymerase chain reaction (PCR) was performed to amplify the specific parts of HBV S gene. In the first step, 685 base paired (bp) region was amplified by sense primer HBMF1 and anti-sense primer HBMR2, while in the second step 485 bp region was amplified by using inner-sense primer HBMF2 and anti-sense primer HBMR2. PCR products were then digested by the restriction enzymes, Alwl, Earl, Hphl, Ncil and NlalV. The RFLP assay indicated that genotype D was the only detected type in our samples. In conclusion, genotype D is the predominant type among hepatitis B patients in our region. RFLP is considered to be an easy and useful method for genotyping HBV strains.

DNA Primers↗
PubMed1995

[Prognostic relevance of hepatitis C virus genotype for responsiveness to interferon-alpha].

The influence of hepatitis C virus (HCV)-genotypes on the responsiveness to interferon- (IFN-alpha) was studied in 116 patients with proven chronic hepatitis C. 88 of 116 (76%) patients were infected with HCV-genotype 1, 7 (6%) with HCV-genotype 2, and 21 patients (18%) with HCV-genotype 3. All patients received at least 3 MU recombinant IFN-alpha-2a, 2b or lymphoblastoid IFN-alpha tiw for at least 6 month (total IFN-alpha dose per patient 216-720 MU, mean 360; treatment duration 6-12 month, mean 8). The follow-up after cessation of therapy was 9-48 months (mean 25). Sustained normalization of the aminotransferase levels was observed in 20 (17%) of the 116 patients. 10 of the 88 (11%) patients with HCV-genotype 1, 7 of the 21 (33%) patients with HCV-genotype 3 (p < 0.02), and 3 out of the 7 patients with HCV-genotype-2- infection achieved a sustained remission. No response was observed in 58 (66%) and 3 (14%) patients with HCV-genotype 1 and 3 infections, respectively (p < 0.002). All but one of the sustained responders remained HCV-RNA negative during the entire follow-up. There were no significant differences between the sustained responders and the group of non-responders and responders with relapse in relation to age, pretreatment aminotransferase levels, histological activity index, or given IFN-alpha dosage. HCV-genotyping is helpful in evaluating the responsiveness to IFN-alpha and will be of importance considering the indication of therapy.

Adult↗