Genotyping of Hepatitis C Virus Isolates from Saudi Patients by Analysis of Sequences from PCR-Amplified Core Region of the Virus Genome

Abstract

We investigated the genotype distribution of hepatitis C virus (HCV) among Saudi patients with chronic hepatitis C. Serum specimens from 119 native Saudi Arabian patients with chronic hepatitis C, as documented by serology and polymerase chain reaction (PCR) for HCV RNA, were used. Genotyping was performed by reverse transcription-PCR, using specific primers at the core region of HCV genome, and DNA sequencing of the resultant amplicons. It was found that the majority of samples (47.9%) belong to genotype 4, followed by subtype 1b (16.8%), and subtype la (10.1%). Twenty samples (16.8%) were not able to be typed by our method. We confirmed the results by cloning at least one PCR amplicon from each genotype, and determining the nucleotide sequence of the clones. Our findings suggest that genotype 4 is the most common among native Saudi Arabian patients with chronic hepatitis C infection. Genotypes lb and la were also prevalent. Ann Saudi Med 1997; 17(6) Hepatitis C virus (HCV) is globally recognized as a major causative agent of posttransfusion and sporadic non-A, non-B hepatitis.1 Infection with HCV could lead to chronicity, with possible progression to hepatocellular carcinoma (HCC), or complications requiring liver transplantation, such as liver cirrhosis.2 HCV genome is a singlestranded RNA with positive polarity. It is approximately 9400 bases, with a long open reading frame encoding four structural proteins and at least six nonstructural proteins. The genome is flanked by untranslated, conserved regions at both the 5' and 3' ends.3 HCV genome exhibits a high degree of sequence variability from one isolate to another. 4As such, HCV has been classified into a number of genotypes and subtypes. [5][6][7] Genotyping of HCV is of clinical relevance to follow-up interferon therapy, [8][9][10][11] and of epidemiological importance in order to investigate transmission routes and geographical clustering. 12,13 In Saudi Arabia, HCV infection is considered endemic, reaching a serological prevalence of up to 5% in individuals over 50 years of age.14 So far, only three studies have described the distribution of HCV genotypes among Saudi blood donors and patients with liver disease or on hemodialysis.15-17 However, most of these studies have used a limited number of specimens, or those from patients with various conditions and blood donors. In this study, we report genotype distribution among 119 serum from Saudi patients with chronic HCV infection, by identifying genotype-specific sequences in the core region of HCV RNA. Materials and MethodsSerum samples were sent to the Virology, Immunology and Infectious Diseases Research Laboratories at the Research Centre of King Faisal Specialist Hospital and Research Centre, for the detection of HCV RNA by the polymerase chain reaction (PCR). All sera showed elevated liver enzymes, tested positive for anti-HCV antibodies by second-generation ELISA, and were confirmed reactive by RIBA-2. The serum samples were from patients diagnosed to have chronic iiepatitis C infection. By using ...

Molecular epidemiology of hepatitis C virus in Iran as reflected by phylogenetic analysis of the NS5B region

“…The subtypes found in Iran, were neither similar to those in neighbouring countries like Turkey or Pakistan, where the dominating subtypes are 1b and 3 [Abacioglu et al, 1995;Shah et al, 1997] nor to those in Middle East countries such as Iraq, Saudi Arabia, Yemen, Kuwait where 4 is the most prevalent HCV genotype [Ohno et al, 1996;Al-Ahdal et al, 1997;Chamberlain et al, 1997;Fakeeh and Zaki, 1999]. The similarities in the distribution of the HCV subtypes in Iran with European countries and the USA might support a common origin through large-scale medical contacts between Iran and these countries.…”

“…These strains might have been introduced from one of the neighbouring Arabic countries, where genotype 4 is prevalent [Al-Ahdal et al, 1997;Chamberlain et al, 1997;Fakeeh and Zaki, 1999] and become spread at dialysis units. Imports of foreign HCV strains from other countries have been documented from South Africa [Smuts and Kannemeyer, 1995].…”

Hepatitis C Virus Genotyping by Polymerase Chain Reaction and DNA Enzyme Immunoassay among Saudi Patients in the Western Province, Saudi Arabia

“…3,17 Only one study in the Kingdom found genotype 3a in two (1.6%) of 119 patients with chronic hepatitis infection. 9 We did not find genotypes 3 and 6 in any of our patients in the Western Province.…”

“…The few published studies have been carried out mainly in institutions in the Riyadh area. [6][7][8][9][10][11][12] The purpose of our study was to determine the prevalent HCV genotypes among HCV seropositive Saudi patients in the Western Province, and to study the relationship between types/subtypes, clinical status and liver histology.…”

Predictors of sustained virological response to a 48-week course of pegylated interferon alfa-2a and ribavirin in patients infected with hepatitis C virus genotype 4

“…However, several recent studies carried out in Europe have indicated changes in genotype distribution and have underlined the increasing prevalence of HCV-4 13–15. The prevalence of HCV antibody positivity in Saudi Arabia ranges from 1% to 3%,1617 with genotype 4 representing 60% to 70% of these infections 18–21. There are limited reports on the treatment of chronic HCV-4 patients from the Middle East (mainly from Saudi Arabia, Egypt, Kuwait, and Qatar),22–31 or elsewhere 32–35.…”