The amygdala is an almond-shaped set of neuronal nuclei located deep within the brain's medial temporal lobe, just anterior to the hippocampus (shown in Figure 1). The amygdala is an important component of the limbic system, a neural network that mediates many aspects of emotional learning and behavior and plays a prominent role in processing of certain emotions, including fear. Abnormal functioning or damage within the amygdala, and the neural circuits that connect it with a variety of cortical and subcortical structures, is thought to contribute to the pathophysiology of a number of neuropsychiatric disorders, such as anxiety, autism and depression.

The transcriptome analysis shows that 81% (n=16293) of all human protein-coding genes (n=20162) are expressed in the human amygdala. Human one-to-one orthologues were investigated in pig and mouse brain, suggesting that 12416 of all mouse one-to-one orthologues (n=16679) are expressed in the mouse amygdala and that 13954 of all pig orthologues (n=16614) are expressed in the pig amygdala.

Gene classification based on regional RNA expression in human, pig and mouse amygdala defines 1 genes as amygdala enriched in either of the three species.

Figure 1. Schematic drawing of the human brain, indicating the location of amygdala from a coronal perspective.

Table 1: Number of genes within the different categories of regionally elevated expression, in human amygdala

The transcriptome analysis shows that 81% (n=16293) of all human proteins (n=20162) are expressed in the amygdala and 22 genes show an elevated expression level in amygdala compared to other regions of the brain.

• 1 regionally enriched genes
• 22 regionally elevated genes in total
• 7 of the amygdala elevated genes are elevated in other tissues than the brain.
• 15 of the amygdala elevated genes are elevated in the brain.

The transcriptome analysis shows that 62% (n=12416) of all mouse one-to-one human orthologue genes (n=16679) are expressed in the amygdala. 38 genes show an elevated expression in amygdala compared to other regions of the brain.

Table 2: Number of genes within the different categories of regionally elevated expression, in amygdala

Figure 2. Schematic drawing of the mouse brain, indicating the location of amygdala from a coronal perspective.

The transcriptome analysis shows that 69% (n=13954) of all pig one-to-one human orthologue genes (n=16614) are expressed in the amygdala. 49 genes show an elevated expression in amygdala compared to other regions of the brain.


Table 3: Number of genes within the different categories of regionally elevated expression, in amygdala

Figure 3. Schematic drawing of the pig brain, indicating the location of amygdala from a coronal perspective or sagittal view.