What is the “warrior” gene?
The “warrior” gene refers to a genetic variant of the MAOA gene that was named due to its association with aggressive behaviour. The MAOA gene encodes the monoamine oxidase A enzyme that breaks down neurotransmitters – chemical messengers involved in transmitting messages from the brain to the rest of the body. Dopamine, norepinephrine and epinephrine are a few examples of such neurotransmitters. Dopamine controls sensations involved in pleasure and reward and epinephrine and norepinephrine influence the flight-or-fight response. The “warrior” gene results in low levels of monoamine oxidase A, disrupting the normal breakdown of these neurotransmitters.

How is the “warrior” gene inherited?
The MAOA gene is located on the X-chromosome. Males inherit only one X chromosome so they have only one version of MAOA. If a male inherits the “warrior” gene, they are more likely to be affected by it. Females have two X chromosomes, hence females can inherit two different versions of the gene. This means that even if a female inherits one copy of the “warrior” gene, they are less likely to be affected as they also carry one normal version of MAOA. It is also possible for females to inherit two copies of the “Warrior” gene, but the affect of this genetic variant on females is not well understood.

Characteristics associated with the “warrior” gene
The “warrior” gene was named due to its association with aggressive behaviour. Since then, studies have linked the warrior gene to various other characteristics including:

• Antisocial behaviour
• Pathological gambling
• Alcoholism
• Personality disorders
• Crime and violence especially when abused as children
• Psychological disorders such as autism, depression, sleep disorders, seizures
  Panic disorders
• Mental retardation (Brunner syndrome)
• Sudden infant death syndrome

Although the “warrior” gene has been linked to many negative characteristics, there is also a strong correlation between “warrior” gene carriers and successful business decisions. Recent studies have shown that people that have one or more copies of the “warrior” gene are more likely to take financial risks and are more likely to benefit from these risks.