Baseline HCMV load i.e. at the initiation of treatment, in whole blood was highest in patients with mixed gB genotype infections (5.37 ± 0.92 log10 genomes/ml) compared to individual gB genotype infections although this was only significant when compared with gB1 and gB2 baseline HCMV loads (4.65 ± 0.93 log 10 genomes/ml (p = 0.0001) and 4.69 ± 0.85 log 10 genomes/ml (p = 0.002) respectively). This evidence concerns the gene GABBR2 and infection.