title: Hepatitis B surface gene variants isolated from blood donors with overt and occult HBV infection in north eastern Egypt.
abstract: BACKGROUND
  Major hydrophilic region in genomic HBV extending from aa99 to aa169, clustered with a highly conformational epitope, is critical to the antigenicity of hepatitis B surface antigen (HBsAg) and may affect the diagnosis of HBV in HBV screening test. So, this study aimed to characterize variants of S gene product of hepatitis B virus (HBV) isolated from patients with overt or occult HBV infection in north-eastern Egypt.
  
  
  METHODS
  The study included sera of two different groups of volunteer blood donors (VBDs), 82 with overt HBV that were positive for HBsAg and anti-HBc and 343 donors negative for HBsAg eligible for donation. Of the latter group, only 44 were positive for anti-HBc. All anti-HBc positive sera were subjected to HBV DNA detection and partial sequence analysis targeting the HBV S gene.
  
  
  RESULTS
  HBV DNA was detected in 22.7 % of HBsAg-/anti-HBc + (10/44 patients) and in 90 % of HBsAg + donors (74/82 patients) with significant statistical difference (P = 0.0001). Phylogenetic analysis showed that HBV strains retrieved from both groups were of genotype D. Amino acid escape mutation T125M was detected in only 2 samples of the occult infection group and in none of the overt group (P = 0.01). Different amino acid substitutions were identified in overt infection group: S143L/T (16.2 %, 12/74) and P120T/S (2.7 %, 2/74). Q129R was significantly more frequent in cases with occult HBV infection (40 %, 4/10) than overt group (6.8 %, 5/74) (P = 0.01).
  
  
  CONCLUSIONS
  HBV genotype D predominated both in patients with overt and occult HBV infection. Different profiles of amino acid substitutions in the major hydrophilic region were seen in these two groups in Egypt.
authors.affiliation: Department of Microbiology and Immunology, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. rankishk@yahoo.com.
authors.forename: Rania
authors.initials: R
authors.lastname: Kishk
authors.affiliation: Department of Endemic and Infectious diseases, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. nadernemr95@yahoo.com.
authors.forename: Nader
authors.initials: N
authors.lastname: Nemr
authors.affiliation: Department of Clinical and Chemical Pathology, Faculty of Medicine, South Valley University, Qena, Egypt. abeer.elkady@gmail.com.|Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, 467-8601, Japan. abeer.elkady@gmail.com.
authors.forename: Abeer
authors.initials: A
authors.lastname: Elkady
authors.affiliation: Department of Clinical Pathology, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. m.fouad452006@yahoo.com.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mandour
authors.affiliation: Department of Endemic and Infectious diseases, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. aboelmagd_tm@yahoo.com.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Aboelmagd
authors.affiliation: Department of Clinical Pathology, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. nramsis@hotmail.com.
authors.forename: Nevene
authors.initials: N
authors.lastname: Ramsis
authors.affiliation: Department of Endemic and Infectious diseases, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. mfmhassan666@yahoo.com.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hassan
authors.affiliation: Department of Endemic and Infectious diseases, Faculty of Medicine, Suez Canal University, El Salam District, Ismaïlia, Egypt. nhawass@yahoo.com.
authors.forename: Nashaat
authors.initials: N
authors.lastname: Soliman
authors.affiliation: Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, 467-8601, Japan. iijima@med.nagoya-cu.ac.jp.
authors.forename: Sayuki
authors.initials: S
authors.lastname: Iijima
authors.affiliation: Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, 467-8601, Japan. s.mura@med.nagoya-cu.ac.jp.
authors.forename: Shuko
authors.initials: S
authors.lastname: Murakami
authors.affiliation: Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, 467-8601, Japan. ytanaka@med.nagoya-cu.ac.jp.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Aljouf University, Sakaka, KSA, Saudi Arabia. mosragh2001@hotmail.com.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Ragheb
mesh_terms: D000328:Adult; D019943:Amino Acid Substitution; D001782:Blood Donors; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D004534:Egypt; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens