The other genome: a systematic review of studies of mitochondrial DNA haplogroups and outcomes of HIV infection and antiretroviral therapy.

Mitochondrial toxicity is implicated in some treatment-limiting antiretroviral therapy complications, and reports of mitochondrial dysfunction in untreated HIV infection suggest antiretroviral therapy independent effects of HIV. Several studies have explored associations between mtDNA haplogroups (patterns of mtDNA polymorphisms) and outcomes of HIV infection and/or antiretroviral therapy, but findings have been inconsistent. We systematically reviewed published studies examining mtDNA haplogroups in HIV-infected persons to summarize reported outcome associations, and to highlight potential future research directions. We identified 21 articles published from 2005-2013. Multiple different phenotypes were studied; most were antiretroviral therapy associated metabolic outcomes (e.g. lipodystrophy, insulin resistance, and dyslipidemia). Haplogroup H was associated with the most outcomes, including AIDS progression, CD4 T-cell recovery, cirrhosis (in hepatitis C coinfection), and metabolic outcomes. This review is the first to focus on the emerging area of mtDNA haplogroups in HIV, and summarizes the published literature on associations between mtDNA haplogroups and clinical outcomes in populations of European and African descent. Several reported associations require replication and ideally biological verification before definitive conclusions can be drawn, but research in this area has the potential to explain outcome disparities and impact clinical management of patients.