Short communication: identification of a novel HIV type 1 subtype H/J recombinant in Canada with discordant HIV viral load (RNA) values in three different commercial assays.
The presence of HIV-1 non-B subtypes is increasing worldwide. This poses challenges to commercial diagnostic and viral load (RNA) monitoring tests that are predominantly based on HIV-1 subtype B strains. Based on phylogenetic analysis of the gag, pol, and env gene regions, we describe the first HIV-1 H/J recombinant in Canada that presented divergent viral load values. DNA sequence analysis of the gag gene region further revealed that genetic diversity between this H/J recombinant and the primers and probes used in the bio-Merieux Nuclisens HIV-1 QT (Nuclisens) and Roche Amplicor Monitor HIV-1, v1.5 (Monitor) viral RNA assays can erroneously lead to undetectable viral load values. This observation appears to be more problematic in the Nuclisens assay. In light of increasing genetic diversity in HIV worldwide we recommend that DNA sequencing of HIV, especially in the gag gene region targeted by primers and probes used in molecular diagnostic and viral load tests, be incorporated into clinical monitoring practices.
Kim
John E
JE
National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, Ontario K1A 0L2, Canada. john_kim@phac-aspc.gc.ca
Beckthold
Brenda
B
Chen
Zhaoxia
Z
Mihowich
Jennifer
J
Malloch
Laurie
L
Gill
Michael John
MJ
D002170:Canada; D003951:Diagnostic Errors; D005838:Genotype; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D019562:Viral Load / Q000379:methods*; D054299:env Gene Products, Human Immunodeficiency Virus / Q000235:genetics; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000235:genetics; D054302:pol Gene Products, Human Immunodeficiency Virus / Q000235:genetics
D012367:RNA, Viral; D054299:env Gene Products, Human Immunodeficiency Virus; D054301:gag Gene Products, Human Immunodeficiency Virus; D054302:pol Gene Products, Human Immunodeficiency Virus