title: Prevalence of hepatitis B virus genotypes in HBsAg positive individuals of Afghanistan.
abstract: BACKGROUND
  The structural and functional differences between hepatitis B virus (HBV) genotypes are the mainstay to severity, complications, treatment and possibly vaccination against the virus. This study was conducted to determine the HBV genotypes in HBsAg positive patients of Afghanistan as no such large scale data available previously.
  
  
  METHODS
  Two hundred and fourteen HBsAg-positive patients were included in this study. All patients were anti-HCV and anti-HIV negative. All the samples were confirmed for HBV DNA with nested PCR while HBV DNA positive samples were subjected to type specific PCR for HBV genotyping (A-F).
  
  
  RESULTS
  Of the total samples, 168 (78.5%) were males and 46 (21.49%) females, aged ranged between 18 to 71 years. This study demonstrated that genotype D (35.67%) is the predominant genotype circulating in Afghani's population. Genotype C was observed in 32.16% followed by genotype A (19.30%), and genotype B (7.02%) while 6.07% of the individuals were not typed.
  
  
  CONCLUSIONS
  This study has shown a heterogeneous distribution of HBV genotypes. Further more, extensive studies are required to investigate genetic and geographical divergence and characteristics of the virus in the country, as no such large sample sized study has been carried out so far in this country.
authors.affiliation: Department of Zoology, Islamia College Peshawar (A Public SectorUniversity), University Campus Peshawar 25120, Khyber Pakhtunkhwa, Pakistan.
authors.forename: Sobia
authors.initials: S
authors.lastname: Attaullah
authors.forename: Saif ur
authors.initials: Su
authors.lastname: Rehman
authors.forename: Sanaullah
authors.initials: S
authors.lastname: Khan
authors.forename: Ijaz
authors.initials: I
authors.lastname: Ali
authors.forename: Sajid
authors.initials: S
authors.lastname: Ali
authors.forename: Shahid Niaz
authors.initials: SN
authors.lastname: Khan
mesh_terms: D000293:Adolescent; D000328:Adult; D000346:Afghanistan / Q000453:epidemiology; D000368:Aged; D004279:DNA, Viral / Q000097:blood / Q000235:genetics; D005260:Female; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology* / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D015995:Prevalence; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens