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Updated: Aug 19, 2026
A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
Published on: August 31, 2014
Emergence of HIV-1 CRF01_AE/B unique recombinant forms in Kuala Lumpur, Malaysia
Kok Keng Tee1, Chee Keong Pon, Adeeba Kamarulzaman
1Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Objectives:
To investigate the molecular epidemiology of HIV-1 and to screen for the emergence of intersubtype recombinants in Kuala Lumpur, Malaysia.
Design:
A molecular epidemiology study was conducted among HIV-1 seropositive patients attending the University Malaya Medical Center (UMMC) from July 2003 to June 2004.
Methods:
Protease (PR) and reverse transcriptase (RT) gene sequences were derived from drug resistance genotyping assay of 100 newly diagnosed or antiretroviral-naive patients. These were phylogenetically analysed to determine the subtypes and recombination breakpoint analyses were performed on intersubtype recombinants to estimate the recombination breakpoint(s).
Results:
CRF01_AE predominated in Kuala Lumpur with 65% in both PR and RT genes. B subtype was detected at 14% and 12% in PR and RT genes, respectively. C subtype was present at 1% in both genes. Overall, the concordance of PR and RT genes in discriminating subtypes/circulating recombinant forms (CRF) was high at 96%. In this study, novel CRF01_AE/B intersubtype recombinants were detected at high prevalence (22%), including those isolates with subtype discordance. Thai variants of CRF01_AE and B subtype were involved in the genesis of these unique recombinant forms (URF). Interestingly, 19 CRF01_AE/B intersubtype recombinant isolates shared similar recombination breakpoints in both PR and RT genes. Several distinct URF were also identified.
Conclusion:
PR and RT genes can be utilized for subtype/CRF assessment with high degree of agreement, allowing concurrent surveillance of circulating HIV-1 subtypes with antiretroviral drug resistance genotyping tests. The emergence of highly identical CRF01_AE/B intersubtype recombinants suggests the possibility of the appearance of a new circulating recombinant form in Kuala Lumpur.
