Table 2.

Genes involved in the pathophysiology of brain edema.

Gene	Principal role	Other diseases related	Potential mechanism of edema formation
APOE	lipid transport and metabolism [46]	cognitive decline, dementia, and Alzheimer’s disease [87, 91], arteriosclerosis, traumatic brain injury, and intracerebral hemorrhage [82, 86, 88]	inflammatory response that disrupts the BBB and contributes to vasogenic edema after acute brain injury [92]
Hp	acute-phase response and antioxidant role by binding and neutralizing hemoglobin in the blood [72, 93]	cardiovascular events [58, 60]	oxidative stress [54], the release of inflammatory cytokines, the breakdown of BBB [55]
AQP	the main water channel found in the brain, cerebral spinal fluid production and regulation	Epilepsy [94], neurological autoimmune diseases[95], diabetes, artherosclerosis[96], cancer [97], peripheral nerves system damage[98]	cytotoxic and vasogenic edema, BBB disruption, micro-vessel damage, and neuronal death[65]
Sur1	upregulation after trauma, ischemia, and hypoxia [99]	diabetes[99], hypoglycemia[100], autoimmune diseases[101]	modulation of astrocyte swelling, a key factor in cytotoxic edema, BBB breakdown and vasogenic edema[73]

APOE – the apolipoprotein gene, Hp- haptoglobin gene, BBB – blood-brain barrier, AQP- aquaporin gene, Sur1- a sulfonylurea receptor and transmembrane protein gene