Fig. 1.

HO-1 (GT)n repeat length and A(-413)T SNP distributions differ between African Americans and Caucasians. HO-1 (GT)n polymorphism allele lengths were determined by PCR and capillary electrophoresis and the HO-1 A(-413)T SNP was determined by TaqMan SNP Genotyping Assay. a Histogram of the number of alleles of each HO-1 (GT)n repeat length for the entire cohort (HIV− and HIV+). The trimodal distribution of HO-1 (GTN)n repeat lengths was divided into short ‘S’, medium ‘M’, and long ‘L’ alleles as depicted in the histogram. b Histogram of the allelic frequency of each HO-1 (GT)n repeat length in Caucasians and African Americans in the entire cohort. Kolmogorov-Smirnov test revealed a significant (p <  0.001) difference in allelic distribution of HO-1 (GT)n repeat lengths between Caucasians and African Americans. c Allelic frequencies and d genotypic frequencies of the A(-413)T SNP in this cohort, revealing significant allelic and genotypic frequency differences between African Americans and Caucasian subgroups by chi-square (p <  0.001). P value: ***p <  0.001