Determining the effect of religious beliefs on the gene expression of VMAT2/SLC18A2

This study aimed to examine the relationship between the expression levels of VMAT genes, which are vesicular monoamine neurotransmitter transporters, and the religious belief structures of religious (n = 30) and secular (n = 30) individuals. Expression levels of VMAT1 and VMAT2 genes were assessed relatively using ΔCq values normalized to the reference gene GAPDH. It was found that VMAT2 gene expression levels were significantly higher in the secular group compared to the religious group. Furthermore, a wider variance was observed among secular individuals (0.05 – 1.00), whereas gene expression levels in the religious group generally remained within the 0.00 – 0.05 range. Significant negative correlations were also found between VMAT2 expression and subdimensions of religiosity, including religious emotion, religious behavior, relationship with God, and religious cognition. Additionally, specific religious practices such as regular prayer, fasting, chanting (dhikr), and participation in religious gatherings were negatively correlated with VMAT2 gene expression. On the other hand, no significant relationship was found between VMAT2 expression and non-religious spiritual practices such as yoga and meditation. Linear regression analyses showed that religiosity level explained 21.7 % of the variance in VMAT2 expression (R² = 0.217). A positive but association was noted between VMAT2 expression and the level of non-belief (R² = 0.033). These findings demonstrate that there are significant associations between VMAT2 gene expression and individuals' religious belief structures and lifestyles. It is particularly suggested that high levels of religiosity may suppress the expression of this gene, which is related to the dopaminergic system, while a secular lifestyle may be associated with higher dopaminergic activity. The results reveal that psychosocial variables can have observable effects at the biological level and provide valuable contributions to the field of neurotheology.