J Viral Hepat 2016; 1–11 wileyonlinelibrary.com/journal/jvh | 1 © 2016 John Wiley & Sons Ltd Received: 21 July 2016 | Accepted: 6 October 2016 DOI: 10.1111/jvh.12631 Summary Hepatts B virus (HBV) is genetcally highly divergent and classifed in ten genotypes and forty subgenotypes in distnct ethno-geographic populatons worldwide. Ethiopia is a country with high HBV prevalence; however, litle is known about the genetc vari- ability of HBV strains that circulate. Here, we characterize the complete genome of 29 HBV strains originatng from fve Ethiopian regions, by 454 deep sequencing and Sanger sequencing. Phylogenetcally, ten strains were classifed as genotype A1 and nineteen as genotype D. Fifeen genotype D strains, provisionally named subgenotype D10, showed a novel distnct cluster supported by high bootstrap value and >4% nu- cleotde divergence from other known subgenotypes. In additon, the novel D10 strains harboured nine unique amino acid signatures in the surface, polymerase and X genes. Seventy-two per cent of the genotype D strains had the precore premature stop codon G1896A. In additon, 63% genotype A and 33% genotype D strains had the basal core promoter mutatons, A1762T/G1764A. Furthermore, four pre-S deleton variants and two recombinants were identfed in this study. In conclusion, we ident- fed a novel HBV subgenotype D10 circulatng in Ethiopia, underlining the high genetc variability of HBV strains in Africa. KEYWORDS Ethiopia, genetc variability, genotype and subgenotypes, hepatts B virus, novel subgenotype D10 1 Department of Viroscience, Erasmus Medical Center, Roterdam, The Netherlands 2 Natonal blood bank services, Ministry of Health, Addis Ababa, Ethiopia 3 Artemis One health, Utrecht, The Netherlands 4 Center for Infecton Medicine and Zoonoses Research, University of Veterinary Medicine, Hannover, Germany 5 ViroClinics BioScience BV, Roterdam, The Netherlands Correspondence Bart L. Haagmans, Department of Viroscience, Erasmus Medical Center, Roterdam, The Netherlands. Email: b.haagmans@erasmusmc.nl Funding informaton Nufc, Grant/Award Number: CF8605 ORIGINAL ARTICLE A novel hepatts B virus subgenotype D10 circulatng in Ethiopia G. B. Hundie 1 | V. Stalin Raj 1 | D. Gebre Michael 2 | S. D. Pas 1 | M. P. Koopmans 1 | A. D. M. E. Osterhaus 3,4 | S. L. Smits 5 | B. L. Haagmans 1 1 | INTRODUCTION Despite advances in preventon, diagnosis and treatment, hepatts B virus (HBV) infecton remains a major global health problem, especially in Africa and Asia, where seroprevalence is high. 1 HBV is the prototype of the family Hepadnaviridae with a partally double-stranded circular DNA genome of 3.2 kb organized into four overlapping open reading frames (ORFs: S, for the surface or envelope gene; C, for the core gene; X, for the regulatory X gene; and P, for the polymerase gene). 2 Because its polymerase lacks proof-reading actvity and its genomes undergo frequent recombinaton, HBV exhibits a high degree of genetc het- erogeneity. 3 To date, ten genotypes, A-J, defned by an intergroup di- vergence of greater than 7.5% over the entre genome sequence have been established. 4-8 Moreover, extensive phylogenetc analyses of HBV genotypes in diferent studies worldwide have identfed several subgenotypes within genotypes, A (A1-A6), B (B1-B9), C (C1-C16), D (D1-D9), F (F1-F4) and I (I1-I2), based on full genome divergence of > 4% but < 7.5%. 4,6,9-14 HBV genotypes and subgenotypes difer in clini- cal and therapeutc outcomes 15,16 and have distnct ethno-geographic distributon worldwide. 6,17 Numerous studies carried out in diferent African countries have also unveiled the emergence of a trend in the geographic distribu- ton of genotypes and subgenotypes. Subgenotype A1 is dominant in Abbreviatons: BCP, basal core promoter; HBV, hepatts B virus; ORF, open reading frames; PC, preCore; RDP, recombinaton detecton program.