Genetic Factors in Aggression

What is the function of the MAOA enzyme?

it breaks down serotonin, dopamine and noradrenaline

What is the relationship between low levels of MAOA and aggression?

Studies show a correlation between low levels of MAOA (MAOA-L) and increased aggression.

What genetic mutation was found in the Dutch family studied by Brunner (1993)?

The family had a MAOA deficiency caused by a mutation on the X chromosome.

What behavioral issues were observed in the males of the Dutch family with MAOA deficiency?

They exhibited impulsive aggression and borderline mental retardation.

What does the diathesis-stress model suggest?

Genetic vulnerabilities may only manifest as behaviors when triggered by environmental stressors.

What is Brunner Syndrome?

A rare condition associated with MAOA deficiency, characterized by low IQ (around 85), impulsive behavior, sleep disorders, and mood swings.

What was the focus of Moffitt's longitudinal study in 1992?

The study monitored MAOA-L levels and abuse in 442 New Zealand males from birth to age 26.

What was the finding of Moffitt's study regarding abuse and MAOA-L levels?

Males who suffered abuse and had MAOA-L were found to be more aggressive.

What did the 1995 study by Cases et al. demonstrate using genetically engineered mice?

Mice missing the MAOA gene exhibited MAOA-L and increased aggression during mating compared to non-engineered mice.

Is there a specific gene identified that causes aggressive behavior?

No specific gene has been found to cause aggressive behavior.

What neurotransmitters build up due to a lack of MAOA?

A lack of MAOA causes serotonin, dopamine, and noradrenaline to build up.