African Americans have more of the super warrior gene or super low MAO-A & African Americans are exposed to more prenatal testosterone as shown by the digit ratio.
2 factors which increase aggression.
https://en.m.wikipedia.org/wiki/Digit_ratio
https://selfhacked.com/blog/about-mao-a-and-what-to-do-if-you-have-the-warrior-gene/
Racial Differences
The Warrior Gene was found to be more or less prevalent in different ethnic groups [6].
The 3R version, which produces less MAO-A, was found in 59% of Black men, 56% of Maori men (an aboriginal New Zealand group), 54% of Chinese men and 34% of Caucasian men.
The 2R version, which produces the least MAO-A, is found in 5.5% of Black men, 0.1% of Caucasian men, and 0.00067% of Asian men.
Aggression and Antisocial Behavior
The basic interpretation is that people with 2R or 3R version may produce less MAO-A and have more circulating adrenaline, dopamine, and serotonin. This is still uncertain [6, 7].
Limited studies found associations between low-activity MAOA variants and a range of aggressive and antisocial behaviors, including adolescent antisocial behavior, reduced social cooperation, physical aggression, criminal violence, and recidivism in male violent offenders. But many of these associations were not properly confirmed [5]
Later studies suggested that low-activity MAOA may predispose people to antisocial behavior in life only if they suffered traumatic events in early life [7].
Other studies found opposite effects in women – they associated high-activity MAOA versions with increased risk of antisocial behavior and aggression. Some scientists have hypothesized that testosterone can modify the impact of MAOA on behavior to explain these findings [5].
One theory proposes that low-activity MAOA variants may be “sensitivity variants” that make carriers more responsive to both negative (trauma) and positive (resilience) factors [5].
In line with this theory, recent findings suggest that certain protective psychosocial factors like resilience may be able to shape a person’s genetic predispositions. That means a low-MAOA carrier might benefit more from a protective, enriched environment – but they may also suffer more from trauma. This has yet to be verified, though [5].
According to a study on Syrian refugees published in 2019, men with low-activity MAOA perceived less stress. The biggest reductions in perceived stress were seen in men with low-activity MAOA with low trauma exposure or