Figure 5From: Combined analysis of circulating β-endorphin with gene polymorphisms in OPRM1, CACNAD2 and ABCB1 reveals correlation with pain, opioid sensitivity and opioid-related side effectsThe genotype frequency of CACNA2D2. The genotype frequency of the CACNA2D2 gene in chronic pain patients with different opioid sensitivity. For further details see Methods and Results.Back to article page