Molecular Epidemiology of Hepatitis B Virus Genotypes and Subgenotypes in Ethnic Minority Populations, Yunnan Province, China

Pharmacogenomic variants in the Pumi population from Yunnan, China

BACKGROUND

Pharmacogenomics is used to identify genetic factors that influence drug responses, thereby optimizing therapeutic outcomes and reducing adverse effects. The objective of this study is to identify pharmacogenomic variations and their clinical relevance to drug metabolism and toxicity within the Pumi population.

METHODS

Eighty-two genetic variants in 43 genes were genotyped in 200 unrelated Pumi individuals using the Agena MassARRAY Assay. Chi-square tests, adjusted for multiple comparisons with Bonferroni correction, were used to compare genotype frequency divergences between the Pumi population and 26 other populations. Population genetic structure diversity and pairwise F-statistics (Fst) were assessed across 27 populations using Structure v2.3.1 and Arlequin v3.5 software.

RESULTS

After Bonferroni correction, a number of single nucleotide variations (SNVs) exhibited significant differences in frequency between the Pumi population and other populations. The allele frequencies of ADH1A rs975833, ADH1B rs1229984, TPMT rs1142345, and CYP2A6 rs8192726 in the Pumi population were notably different from the East Asian population or the other 26 populations. PharmGKB data indicate that rs1229984, rs1142345, and rs8192726 are associated with the metabolic efficiency of acetaldehyde, mercaptopurine, and efavirenz, respectively. Additionally, the genetic structure analysis (K = 5) and pairwise Fst calculations revealed that the Pumi population shared a similar genetic background with CHB (Fst = 0.031), JPT (Fst = 0.033), KHV (Fst = 0.035), CHS (Fst = 0.036), and CDX (Fst = 0.037) populations.

CONCLUSION

Our findings reveal unique genetic variations and biomarkers within the Pumi population, which contributes pharmacogenomic insights and theoretical foundations for personalized medicine tailored to the Pumi population.

HCV and HBV genotypes: vital in the progression of HCV/ HBV co-infection

BACKGROUND

Viral hepatitis is the major contributor to liver cirrhosis and hepatocellular carcinoma (HCC). Studies indicated that the co-infection of hepatitis C and hepatitis B virus also prompts liver damage progression. Therefore, in the present study, the prevalence of HCV-HBV co-infection and the impact of HCV-HBV co-infection on the progression of liver damage was evaluated amongst the HCV-infected patients in Pakistan.

METHODS

In this study 2500 HCV-positive patients were recruited from Pakistan. The presence and prevalence of HCV and HBV was confirmed through ELISA and nested PCR. To determine the liver damage due to viral infection levels of ALT, ALP, and total bilirubin were also determined. Diagnostic history of patients was thoroughly documented through serological tests and liver biopsy reports. Viral genotypes and viral loads were determined through multiplex polymerase chain reaction (PCR) and time PCR, respectively.

RESULTS

The study outcomes showed that 12.5% of the HCV-infected patients were co-infected with HBV. Co-infection development was more common in females than in males, and females were at a higher risk of developing the infection (p-value = < 0.0001, OR = 2.437). Despite the variation among different age groups, there was no significant difference in co-infection prevalence. HCV genotype 3a was found to be most prevalent while in HBV genotype D was found to be prevalent among the patients. The HCV patients frequently developed co-infection with HBV genotype D. It was also determined that viral load for HBV genotype D was higher compared to non-D genotypes while for HCV viral load was higher in non-3a genotypes.

CONCLUSIONS

This study evaluated the prevalence of HCV and HBV co-infection among HCV-positive patients, revealing that 12.5% patients were co-infected with HBV. Co-infection was more common in females, who had a higher risk of developing it. The study also revealed that HBV genotype D was the most prevalent in co-infected patients, with no significant age-related differences in co-infection rates.

Prevalence and Trends of Transfusion-Transmissible HBV Infection Among Blood Donors in Southwestern China: A Six-Year Retrospective Study

Objective

Hepatitis B virus (HBV) infection is a significant global public health concern, with variable prevalence rates across regions. The prevalence of transfusion-transmitted HBV infection (TT-HBV) via donated blood necessitates an evaluation of blood safety and potential risks to the population. This study assessed the prevalence of HBV infection among blood donors in Southwestern China over 6 years.

Methods

We analyzed 903,023 blood donations from a central blood center in Southwestern China between January 2017 and December 2022. The prevalence of HBV in donations was determined for one-time and repeat donors, considering birth cohorts and covariates. Demographic characteristics, donation frequency, and anti-HBV antibody status were analyzed to estimate the incidence of TT-HBV.

Results

One-time donors provided 47.78% of the samples, and 52.22% were from repeat donors. The HBV prevalence decreased from 1.0% in 2017 to 0.87% in 2022 in one-time donors and from 0.30% to 0.09%, respectively, in repeat donors. A significantly lower HBV prevalence was identified in the post-1992 birth cohort (0.33%) than in the pre-1992 birth cohort (1.67%). The estimated incidences of TT-HBV occurring from one-time donors, repeat donors, post-1992 birth cohort donors, and pre-1992 birth cohort donors were 20.76, 13.84, 0.82, and 20.98 per 104 person-years, respectively.

Conclusion

Our findings indicate a decreasing trend in HBV prevalence among blood donors in Southwestern China over the 6-year study period. This decline may be attributed to the widespread administration of HBV vaccinations and stringent screening measures implemented by blood donation centers. Continuous monitoring for HBV among blood donors is necessary to evaluate the effectiveness of preventive measures and inform future strategies to reduce transmission.

Hepatitis B virus genotype surveillance in Canadian blood donors and a referred patient population, 2016-2021

BACKGROUND AND OBJECTIVES

Hepatitis B virus (HBV) genotypes (A-H) have a distinct geographic distribution and are highly associated with the country of birth. Canada has experienced increased immigration over the past decade, primarily from regions where HBV is endemic. This study investigated the proportions and trends of HBV genotypes within blood donor and clinical populations of Canada over the period 2016-2021.

MATERIALS AND METHODS

Study samples involved two cohorts: (1) Canadian blood donors (n = 246) deferred from donation due to HBV test positivity and (2) chronic HBV patients from across Canada (clinically referred population, n = 3539). Plasma or serum was extracted, and the surface antigen and/or polymerase-coding region was amplified and sequenced to determine genotype by phylogenetic analysis.

RESULTS

Six (A-E, G) and eight (A-H) HBV genotypes were detected among deferred blood donors and the clinically referred population, respectively. Differences in HBV genotype proportions between the two cohorts were observed across Canada. Males comprised most of the referred population among genotypes A-E (p < 0.0001), except for genotypes B and C. The median age was younger among blood donors (36 years [range 17-72]) compared with the referred population (41 years [range 0-99]). Distinct trends of increasing (E, referred; B, blood donor) and decreasing genotype prevalence were observed over the study period.

CONCLUSION

HBV genotypes in Canada are highly diverse, suggesting a large immigrant population. Observed trends in genotype prevalence and proportional differences among cohorts imply shifts among the HBV-infected population of Canada, which warrants continued surveillance.

Concealed for a Long Time on the Marches of Empires: Hepatitis B Virus Genotype I

Genotype I, the penultimate HBV genotype to date, was granted the status of a bona fide genotype only in the XXIst century after some hesitations. The reason for these hesitations was that genotype I is a complex recombinant virus formed with segments from three original genotypes, A, C, and G. It was estimated that genotype I is responsible for only an infinitesimal fraction (<1.0%) of the chronic HBV infection burden worldwide. Furthermore, most probably due to its recent discovery and rarity, the natural history of infection with genotype I is poorly known in comparison with those of genotypes B or C that predominate in their area of circulation. Overall, genotype I is a minor genotype infecting ethnic minorities. It is endemic to the Southeast Asian Massif or Eastern Zomia, a vast mountainous or hilly region of 2.5 million km2 spreading from Eastern India to China, inhabited by a little more than 100 million persons belonging primarily to ethnic minorities speaking various types of languages (Tibeto-Burman, Austroasiatic, and Tai-Kadai) who managed to escape the authority of central states during historical times. Genotype I consists of two subtypes: I1, present in China, Laos, Thailand, and Vietnam; and I2, encountered in India, Laos, and Vietnam.

A Recent Prevalence of Hepatitis B Virus (HBV) Genotypes and Subtypes in Asia: A Systematic Review and Meta-Analysis

Background and Aim: Despite introducing the hepatitis B virus (HBV) vaccine, the incidence of the Hepatitis B virus globally is still a major health concern. This systematic review and meta-analysis were conducted to provide detailed information on the prevalence of HBV genotypes and subtypes in circulation in Asia. Methods: A systematic search for articles describing the prevalence of HBV genotypes and subtypes in Asia was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Results: Our search returned 207 eligible articles involving 49,279 genotypes and 7457 subtypes representing 28 Asian countries. A meta-analysis was performed on our eligible studies using the Random effect Model. The pooled prevalence of HBV genotypes showed that genotype C (30.9%) (95% CI, 27.5–34.5%; I2 = 97.57%; p < 0.001) was the most common HBV genotype in Asia, followed by genotype B (17.8%) (95% CI, 15.5–20.4%; I2 = 97.26%; p < 0.001) and genotype D (15.4%) (95% CI, 11.8–19.8%). Vietnam had the highest prevalence of genotype B, Lebanon had the highest prevalence of genotypes C, and Jordan had the highest prevalence of genotype D. There was variation in genotypic prevalence with respect to the target genes for HBV genotyping. Reverse dot blot hybridization had the highest estimate of genotypes B and C. HBV subtype C2 (40.0%) (95% CI, 33.3–47.0) is the most prevalent HBV subtype. Conclusion: Evidence from this study reveals that HBV genotypes C and B are the most dominant HBV genotypes in Asia, and HBV subtype C2 is more endemic in Asia.