Identification of a New HIV-1 Circulating Recombinant Form CRF112_01B Strain in Baoding City, Hebei Province, China

Background: A large number of HIV-1 recombinants that originated from CRF01_AE and B strains are constantly emerging in men who have sex with men populations in China and deserve more attention and further monitoring. Objective: To analyze the near-full-length genome structure and recombination characteristics of a new HIV-1 strain (BD226AJ) detected in Baoding City and determine its subtype. Case Representation: Viral RNA was extracted from a blood sample collected from an infected individual and reverse transcribed to cDNA. Two overlapping segments of the HIV-1 genome were amplified using a near-endpoint dilution method and sequenced. Recombinant breakpoints were determined using RIP, jpHMM, and SimPlot 3.5.1 software. MEGA v6.0 was used to construct a neighbor-joining phylogenetic tree to determine the homology relationships of this strain. Results and Discussion: We obtained 8830 nucleotides (nt) of the HIV-1 genome sequence by amplification and sequencing, and four recombinant fragments were identified by recombination analysis, namely CRF01_AE (HXB2, 823–4224 nt), subtype B (HXB2, 4225–5991 nt), CRF01_AE (HXB2, 5992–9295 nt), and subtype B (HXB2, 9296–9406 nt). The BLAST results showed that 96% of the sequence was similar to CRF112_01B. The jpHMM results confirmed that BD226AJ was the CRF112_01B strain. Conclusion: Our results confirm the first epidemic of CRF112_01B in Hebei Province. This finding suggests that HIV-1 CRF112_01B may have been introduced into Hebei by men who have sex with men and indicates that the epidemic trend of this strain should be closely monitored.