RT Journal Article SR Electronic(1) A1 Fang, Zhong-Liao A1 Hué, Stéphane A1 Sabin, Caroline A. A1 Li, Guo-Jian A1 Yang, Jin-Ye A1 Chen, Qin-Yan A1 Fang, Kong-Xiong A1 Huang, Jian A1 Wang, Xue-Yan A1 Harrison, Tim J.YR 2011 T1 A complex hepatitis B virus (X/C) recombinant is common in Long An county, Guangxi and may have originated in southern China JF Journal of General Virology, VO 92 IS 2 SP 402 OP 411 DO https://doi.org/10.1099/vir.0.026666-0 PB Microbiology Society, SN 1465-2099, AB Recently, a complex (X/C) hepatitis B virus (HBV) recombinant, first reported in 2000, was proposed as a new genotype; although this was refuted immediately because the strains differ by less than 8 % in nucleotide distance from genotype C. Over 13.5 % (38/281) of HBV isolates from the Long An cohort in China were not assigned to a specific genotype, using current genotyping tools to analyse surface ORF sequences, and these have about 98 % similarity to the X/C recombinants. To determine whether this close identity extends to the full-length sequences and to investigate the evolutionary history of the Long An X/C recombinants, 17 complete genome sequences were determined. They are highly similar (96–99 %) to the Vietnamese strains and, although some reach or exceed 8 % nucleotide sequence difference from all known genotypes, they cluster together in the same clade, separating in a phylogenetic tree from the genotype C branch. Analysis of recombination reveals that all but one of the Long An isolates resembles the Vietnamese isolates in that they result from apparent recombination between genotype C and a parent of unknown genotype (X), which shows similarity in part to genotype G. The exception, isolate QL523, has a greater proportion of genotype C parent. Phylogeographic analysis reveals that these recombinants probably arose in southern China and spread later to Vietnam and Laos., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.026666-0