Table 2.

Genes for other neuromodulators of motivated behaviors that differ in VTA in the Low and High Dopamine groups.

Gene ID	Gene	Function	Group diff.	p value
HDC	Histidine decarboxylase	Enzyme, catalyzes histamine production	High > Low	0.004
HNMT	Histamine N-methyltransferase	Enzyme, inactivates histamine	High > Low	0.005
VIP	Vasoactive intestinal peptide	Neuropeptide	High > Low	0.006
MC4R	Melanocortin 4 Receptor	Melanocortin receptor	High > Low	0.016
MTNR1B	Melatonin Receptor 1B	Melatonin receptor	High > Low	0.036
NPY5R	Neuropeptide Y Receptor Y5	NPY and peptide YY receptor	High > Low	0.040
MC3R	Melanocortin 3 Receptor	Melanocortin receptor	High > Low	0.042
HRH1	Histamine Receptor H1	Histamine receptor	Low > High	0.007
HTR1B	5-Hydroxytryptamine Receptor 1B	Serotonin receptor	Low > High	0.011