Table 3. Candidate HKGs in NormFinder evaluation.

Rank	Temporal Cortex		Frontal Cortex		Hippocampus		Hypothalamus		Total
	Gene	Stab. Value	Gene	Stab. Value	Gene	Stab. Value	Gene	Stab. Value	Gene	Stab. Value
1	ACTB	0.061	GAPDH	0.053	HPRT	0.051	GAPDH	0.019	GAPDH	0.019
2	GAPDH	0.063	ACTB	0.053	β2M	0.053	β2M	0.034	HPRT	0.045
3	β2M	0.103	18S	0.069	ACTB	0.062	ACTB	0.051	β2M	0.048
4	HPRT	0.105	HPRT	0.087	GAPDH	0.076	HPRT	0.053	ACTB	0.077
5	18S	0.149	β2M	0.102	18S	0.133	18S	0.089	18S	0.124

Ranking of candidate HKGs by NormFinder for each brain structure and all structures together, as described by the total M-value. Lower stability values indicate more stable genes. A cut-off value of 0.15 was used.