Observed TNFα promoter haplotypes and frequencies in HIV-1 infected patient groups.

Five of the common Caucasian ancestral TNFα promoter SNPs were typed by sequencing and confirmed by RFLP analysis. Statistical analysis was based on the total number of haplotypes (2n) within each group. P values were calculated using the Fisher’s exact test. Statistically significant values are shown in bold. The −237A promoter haplotype was exclusively observed in patients who carried HLA-B*5701.