In a different set of 12 AAA cases and 12 similarly-aged controls (case mean = 69.9 +/- 10.2 y; control mean = 64.3 +/- 14 y; P = 0.27; Additional file 2, Table S2) real-time quantitative RT-PCR was used to confirm the decrease in HOXA4 mRNA expression (P < 0.00004; Figure 3). This evidence concerns the gene HOXA4 and triple-A syndrome.