PURPOSE - Saliva is a good source of DNA for genomic research, and leukocytes are a predominant source of DNA in human saliva. Advanced human immunodeficiency virus (HIV)-type 1 infection disrupts tonsillar architecture and depletes tonsillar lymphocytes. We tested whether HIV-1 infection reduces extracted human DNA yield from saliva.
METHODS - Approximately 2 mL of expectorated saliva was collected from HIV-infected adults during routine primary care clinic visits and from healthy, HIV-negative controls. Human DNA was manually extracted and was specifically quantified by assaying for the RNAse P gene.
RESULTS - Seventy-five individuals were studied, including 25 HIV-infected adults with <200 CD4+ T cells/mm(3) (i.e., acquired immunodeficiency syndrome), 25 with >200 CD4+ T cells/mm3, and 25 HIV-negative controls. Overall DNA yield was 64.7 microg [29.0-139.7 microg] (median [interquartile range]). Yields were comparable among HIV-infected individuals with lower CD4+ T cell counts (74.3 microg [39.4-151.4 microg]), higher CD4+ T cell counts (63.9 microg [29.2-172.1 microg]), and HIV-negative controls (61.4 microg [28.4-123.4 microg]) (p > .05).
CONCLUSION - Infection with HIV-1 does not reduce human DNA yield from saliva. Expectorated saliva should provide sufficient extracted native DNA for genomic studies in HIV-infected individuals.