the maoa gene is associated with aggression, certain alleles frequencies are associated with increased aggression. interestingly, the varying frequencies of these genes and largely influenced by race, and the usual frequencies for each racial group and their impact are exactly as you would expect.  this connects to a far larger issue which debunks the left wing idea that race isn't influenced by genetics. although humans share a lot of genes regardless of race, therefore allowing leftists to deny the existence of genetic races, the frequencies of the alleles within the genes vary dramatically and certain allele frequencies are heavily associated with certain ethnic groups, thus proving genetic differences between the races and thus proving that differences in personality and behavior between the races are genetic in origin.
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